Items tagged with dsolve

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i want to solve this equation,

y''(x)=5*exp(-10/y'(x)) on ]0,15[ with y(0)=0,y(15)=2 

can any one help me ? thank you

Respected member!

Please help me in finding the solution of this problem....
 

NULL

 

 

NULL

>   

``

NULL

restart

with(RealDomain):

r := .2:

k := 5;

5

(1)

BCSforNum1 := u(0) = 0, (D(u))(0) = 1+beta*(((D@@2)(u))(0)-(D(u))(0)*RealDomain:-`^`(k, -1)), (D(u))(m) = 0, ((D@@2)(u))(m) = 0;

u(0) = 0, (D(u))(0) = 1+.2*((D@@2)(u))(0)-0.4000000000e-1*(D(u))(0), (D(u))(6) = 0, ((D@@2)(u))(6) = 0

 

v(0) = 1, v(6) = 0

(2)

numsol1 := dsolve({BCSforNum1, BCSforNum2, ODEforNum1, ODEforNum2}, numeric, output = listprocedure)

Error, (in dsolve/numeric/bvp) initial Newton iteration is not converging

 

``


 

Download mplprimes.mw

I need help with these two questions. anything is helpful

3.mw

There are 2 questions actually. The first as the title says is about taking the integral. I have 2 functions that were found numerically from the system of differential equations (see the file), and I need to take the integral of the expression that includes both of them. Maple gives me something like Int () = Int (), so it doesn't solve anything. Why can it be?

The second question is about varying the boundary conditions. If, for example, I have the system with the condition like R(x_0)=R_0, can I get the plot  of R(x,R_0)? In my case I need to vary conditions on R and mu (R(0)=R_0 and mu(0)=mu_0) and then get the plot of the integral in relation to R_0 and mu_0. Is it even possible?

Dear sir,

I tried to solve a fourth order problem. But I got the error message as better to use midpoint method. Can I know what is midpoint method and here I uploading the problem please verify it if I did anything mistake?program.mw

mar.mw
hi..how i can dsolve these differential equations? omega is unknown and fir solving i add an extra boundary condition, but the error "unable to store %1 when datatype=%2" is appear!!!

how i can remove this error?

thanks

dsys3 := {-6*(diff(f5(x), x, x))+2*f3(x)-(22/3)*f5(x)*omega^2-(2/3)*f4(x)*omega^2+(1/3)*(diff(f1(x), x))*omega^2-(2/3)*(diff(f2(x), x))*omega^2-(14/5)*(diff(f2(x), x, x, x, x, x))+(56/5)*(diff(f5(x), x, x, x, x)), (13/1800)*(diff(f3(x), x, x, x, x, x, x, x, x))+(154/5625)*(diff(f3(x), x, x, x, x, x, x))-(475051/67500)*(diff(f3(x), x, x, x, x))-(2491/4500)*(diff(f1(x), x, x, x, x, x))+(1648/1125)*(diff(f2(x), x, x, x, x, x))-(427/375)*(diff(f1(x), x, x, x))+(24/125)*(diff(f2(x), x, x, x))-(953/375)*(diff(f3(x), x, x))+(28/25)*(diff(f4(x), x, x, x, x)), -6*(diff(f4(x), x, x))-2*f3(x)-(22/3)*f4(x)*omega^2-(2/3)*f5(x)*omega^2+(2/3)*(diff(f1(x), x))*omega^2-(1/3)*(diff(f2(x), x))*omega^2-(44/625)*(diff(f3(x), x, x, x, x, x, x))-(422/75)*(diff(f1(x), x, x, x, x, x))-(28/75)*(diff(f2(x), x, x, x, x, x))+(72/5)*(diff(f4(x), x, x, x, x))+(8/25)*(diff(f3(x), x, x, x, x))-(8/3)*(diff(f2(x), x, x, x))+(8/3)*(diff(f1(x), x, x, x)), (583/30)*(diff(f2(x), x, x, x, x))-2*(diff(f3(x), x))+4*f2(x)-4*f1(x)-(22/3)*f2(x)*omega^2+(2/3)*(diff(f5(x), x))*omega^2-(1/6)*(diff(f1(x), x, x))*omega^2+(1/3)*(diff(f4(x), x))*omega^2+(1/3)*(diff(f2(x), x, x))*omega^2-(2/3)*f1(x)*omega^2+(929/150)*(diff(f1(x), x, x, x, x))+(517/900)*(diff(f3(x), x, x, x, x, x))-(133/75)*(diff(f1(x), x, x, x, x, x, x))-(152/75)*(diff(f2(x), x, x, x, x, x, x))-(9/25)*(diff(f3(x), x, x, x))+(724/45)*(diff(f1(x), x, x))-(724/45)*(diff(f2(x), x, x))-(16/3)*(diff(f4(x), x, x, x))-(14/225)*(diff(f3(x), x, x, x, x, x, x, x)), -(22/3)*f1(x)*omega^2-(2/3)*f2(x)*omega^2-(1/6)*(diff(f2(x), x, x))*omega^2-(1/3)*(diff(f5(x), x))*omega^2-(2/3)*(diff(f4(x), x))*omega^2+(1/3)*(diff(f1(x), x, x))*omega^2-(224/25)*(diff(f1(x), x, x, x, x, x, x))-(12/5)*(diff(f3(x), x, x))-(733/300)*(diff(f3(x), x, x, x))-(1/3)*(diff(f3(x), x, x, x, x))-4*(diff(f2(x), x, x, x))+(24/25)*(diff(f2(x), x, x, x, x))-(133/75)*(diff(f2(x), x, x, x, x, x, x))+(689/900)*(diff(f3(x), x, x, x, x, x))-(6743/31500)*(diff(f3(x), x, x, x, x, x, x, x))+(16/3)*(diff(f4(x), x, x, x))+4*f1(x)-(1036/75)*(diff(f1(x), x, x))-4*(diff(f1(x), x, x, x))+(337/50)*(diff(f1(x), x, x, x, x))-4*f2(x)+(724/45)*(diff(f2(x), x, x))-2*(diff(f3(x), x)), -(14/5)*((D@@3)(f2))(0)+(56/5)*((D@@2)(f5))(0) = 0, -(14/5)*((D@@3)(f2))(1)+(56/5)*((D@@2)(f5))(1) = 0, -(44/625)*((D@@4)(f3))(0)-(8/5)*((D@@3)(f1))(0)-(28/75)*((D@@3)(f2))(0)+(72/5)*((D@@2)(f4))(0)+(8/25)*((D@@2)(f3))(0)-(8/3)*(D(f2))(0)+(8/3)*(D(f1))(0) = 0, (13/1800)*((D@@4)(f3))(0)-(97/4500)*((D@@2)(f3))(0)+(1/9)*(D(f1))(0)-(1/9)*(D(f2))(0)-(31/150)*((D@@2)(f4))(0)+(49/225)*((D@@3)(f1))(0)+(14/225)*((D@@3)(f2))(0) = 0, -(44/625)*((D@@4)(f3))(1)-(8/5)*((D@@3)(f1))(1)-(28/75)*((D@@3)(f2))(1)+(72/5)*((D@@2)(f4))(1)+(8/25)*((D@@2)(f3))(1)-(8/3)*(D(f2))(1)+(8/3)*(D(f1))(1) = 0, (13/1800)*((D@@4)(f3))(1)-(97/4500)*((D@@2)(f3))(1)+(1/9)*(D(f1))(1)-(1/9)*(D(f2))(1)-(31/150)*((D@@2)(f4))(1)+(49/225)*((D@@3)(f1))(1)+(14/225)*((D@@3)(f2))(1) = 0, (109/10)*((D@@2)(f1))(0)+(263/300)*((D@@3)(f3))(0)-(922/75)*((D@@4)(f1))(0)-(133/75)*((D@@4)(f2))(0)+(32/15)*((D@@2)(f2))(0)-(167/75)*(D(f3))(0)+(862/75)*((D@@3)(f4))(0)-(6743/31500)*((D@@5)(f3))(0) = 0, (109/10)*((D@@2)(f1))(1)+(263/300)*((D@@3)(f3))(1)-(922/75)*((D@@4)(f1))(1)-(133/75)*((D@@4)(f2))(1)+(32/15)*((D@@2)(f2))(1)-(167/75)*(D(f3))(1)+(862/75)*((D@@3)(f4))(1)-(6743/31500)*((D@@5)(f3))(1) = 0, -(13/1800)*((D@@5)(f3))(0)-(6/125)*((D@@3)(f3))(0)+(16697/4500)*(D(f3))(0)-(143/300)*((D@@2)(f1))(0)-(373/225)*((D@@2)(f2))(0)+(31/150)*((D@@3)(f4))(0)-(49/225)*((D@@4)(f1))(0)-(14/225)*((D@@4)(f2))(0) = 0, -(13/1800)*((D@@5)(f3))(1)-(6/125)*((D@@3)(f3))(1)+(16697/4500)*(D(f3))(1)-(143/300)*((D@@2)(f1))(1)-(373/225)*((D@@2)(f2))(1)+(31/150)*((D@@3)(f4))(1)-(49/225)*((D@@4)(f1))(1)-(14/225)*((D@@4)(f2))(1) = 0, (189/10)*((D@@2)(f2))(0)+(23/10)*((D@@2)(f1))(0)+(139/300)*((D@@3)(f3))(0)-(133/75)*((D@@4)(f1))(0)-(112/75)*((D@@4)(f2))(0)+(13/75)*(D(f3))(0)+(28/15)*((D@@3)(f4))(0)+(14/5)*((D@@3)(f5))(0)-(14/225)*((D@@5)(f3))(0) = 0, (189/10)*((D@@2)(f2))(1)+(23/10)*((D@@2)(f1))(1)+(139/300)*((D@@3)(f3))(1)-(133/75)*((D@@4)(f1))(1)-(112/75)*((D@@4)(f2))(1)+(13/75)*(D(f3))(1)+(28/15)*((D@@3)(f4))(1)+(14/5)*((D@@3)(f5))(1)-(14/225)*((D@@5)(f3))(1) = 0, -(13/1800)*((D@@8)(f3))(0)-(154/5625)*((D@@6)(f3))(0)+(475051/67500)*((D@@4)(f3))(0)+(2491/4500)*((D@@5)(f1))(0)-(1648/1125)*((D@@5)(f2))(0)+(427/375)*((D@@3)(f1))(0)-(24/125)*((D@@3)(f2))(0)+(953/375)*((D@@2)(f3))(0)-(28/25)*((D@@4)(f4))(0) = 0, -(13/1800)*((D@@8)(f3))(1)-(154/5625)*((D@@6)(f3))(1)+(475051/67500)*((D@@4)(f3))(1)+(2491/4500)*((D@@5)(f1))(1)-(1648/1125)*((D@@5)(f2))(1)+(427/375)*((D@@3)(f1))(1)-(24/125)*((D@@3)(f2))(1)+(953/375)*((D@@2)(f3))(1)-(28/25)*((D@@4)(f4))(1) = 0, (13/1800)*((D@@6)(f3))(0)+(154/5625)*((D@@4)(f3))(0)-(111533/33750)*((D@@2)(f3))(0)-(2491/4500)*((D@@3)(f1))(0)+(1648/1125)*((D@@3)(f2))(0)-(212/375)*(D(f1))(0)+(212/375)*(D(f2))(0)+(152/125)*((D@@2)(f4))(0)-(31/150)*((D@@4)(f4))(0)+(49/225)*((D@@5)(f1))(0)+(14/225)*((D@@5)(f2))(0) = 0, (13/1800)*((D@@6)(f3))(1)+(154/5625)*((D@@4)(f3))(1)-(111533/33750)*((D@@2)(f3))(1)-(2491/4500)*((D@@3)(f1))(1)+(1648/1125)*((D@@3)(f2))(1)-(212/375)*(D(f1))(1)+(212/375)*(D(f2))(1)+(152/125)*((D@@2)(f4))(1)-(31/150)*((D@@4)(f4))(1)+(49/225)*((D@@5)(f1))(1)+(14/225)*((D@@5)(f2))(1) = 0, f1(0) = 0, f1(1) = 0, f2(0) = 0, f2(1) = 0, f4(0) = 0, f4(1) = 0, f5(0) = 0, f5(1) = 0, ((D@@2)(f1))(0) = 0, ((D@@2)(f1))(1) = 0, ((D@@2)(f2))(0) = 0, ((D@@2)(f2))(1) = 0}:

dsys4 := subs(omega^2 = omega2, dsys3):

Typesetting:-mrow(Typesetting:-mo("for", bold = "true", font_style_name = "2D Input", mathvariant = "bold", fontweight = "bold", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mi("bb", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo("in", bold = "true", font_style_name = "2D Input", mathvariant = "bold", fontweight = "bold", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mi("extra_bcs", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo("do", bold = "true", font_style_name = "2D Input", mathvariant = "bold", fontweight = "bold", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(":", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "newline"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo("try", bold = "true", font_style_name = "2D Input", mathvariant = "bold", fontweight = "bold", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(":", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "newline"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "auto"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mi("print", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("bb", italic = "true", font_style_name = "2D Input", mathvariant = "italic")), font_style_name = "2D Input", mathvariant = "normal"), Typesetting:-mo(":", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "newline"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mi("res", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("bb", italic = "true", font_style_name = "2D Input", mathvariant = "italic")), font_style_name = "2D Input", mathvariant = "normal", open = "[", close = "]"), Typesetting:-mo("≔", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mi("dsolve", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("dsys4", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo("union", bold = "true", font_style_name = "2D Input", mathvariant = "bold", fontweight = "bold", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("bb", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo("=", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mn(".00000000001", font_style_name = "2D Input", mathvariant = "normal")), font_style_name = "2D Input", mathvariant = "normal", open = "{", close = "}"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(",", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "true", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.3333333em"), Typesetting:-mi("numeric", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo(",", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "true", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.3333333em"), Typesetting:-mi("output", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo("=", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mi("listprocedure", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo(",", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "true", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.3333333em"), Typesetting:-mi("initmesh", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo("=", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mn("3024", font_style_name = "2D Input", mathvariant = "normal"), Typesetting:-mo(",", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "true", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.3333333em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mi("abserr", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo("=", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mn("1e−5", font_style_name = "2D Input", mathvariant = "normal")), font_style_name = "2D Input", mathvariant = "normal"), Typesetting:-mo(";", font_style_name = "2D Input", mathvariant = "normal", fence = 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separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(":", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "newline"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "auto"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mi("print", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("lasterror", italic = "true", font_style_name = "2D Input", mathvariant = "italic")), font_style_name = "2D Input", mathvariant = "normal"), Typesetting:-mo(":", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "newline"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo("end", bold = "true", font_style_name = "2D Input", mathvariant = "bold", fontweight = "bold", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo("try", bold = "true", font_style_name = "2D Input", mathvariant = "bold", fontweight = "bold", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(":", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "newline"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo("end", bold = "true", font_style_name = "2D Input", mathvariant = "bold", fontweight = "bold", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo("do", bold = "true", font_style_name = "2D Input", mathvariant = "bold", fontweight = "bold", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo(":", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mi("indx", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mo("≔", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mi("indices", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("res", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo(",", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "true", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.3333333em"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mi("nolist", italic = "true", font_style_name = "2D Input", mathvariant = "italic")), font_style_name = "2D Input", mathvariant = "normal"), Typesetting:-mo(";", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "true", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.2777778em"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "newline"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "auto"), Typesetting:-mi("nops", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("indx", italic = "true", font_style_name = "2D Input", mathvariant = "italic")), font_style_name = "2D Input", mathvariant = "normal", open = "[", close = "]")), font_style_name = "2D Input", mathvariant = "normal"), Typesetting:-mo(":", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "newline"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "auto"), Typesetting:-mi("res", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("indx", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mn("1", font_style_name = "2D Input", mathvariant = "normal")), font_style_name = "2D Input", mathvariant = "normal", open = "[", close = "]")), font_style_name = "2D Input", mathvariant = "normal", open = "[", close = "]"), Typesetting:-mo(":", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mspace(height = "0.0ex", width = "0.0em", depth = "0.0ex", linebreak = "newline"), Typesetting:-mo(" ", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.0em"), Typesetting:-mi("Sol", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo("≔", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mi("seq", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("subs", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("res", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("indx", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("i", italic = "true", font_style_name = "2D Input", mathvariant = "italic")), font_style_name = "2D Input", mathvariant = "normal", open = "[", close = "]")), font_style_name = "2D Input", mathvariant = "normal", open = "[", close = "]"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mn("0", font_style_name = "2D Input", mathvariant = "normal")), font_style_name = "2D Input", mathvariant = "normal"), Typesetting:-mo(",", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "true", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.3333333em"), Typesetting:-mi("omega2", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mn("0", font_style_name = "2D Input", mathvariant = "normal")), font_style_name = "2D Input", mathvariant = "normal")), font_style_name = "2D Input", mathvariant = "normal"), Typesetting:-mo(",", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "true", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.3333333em"), Typesetting:-mi("i", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mo("=", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2777778em", rspace = "0.2777778em"), Typesetting:-mn("1", font_style_name = "2D Input", mathvariant = "normal"), Typesetting:-mo("..", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "false", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.2222222em", rspace = "0.0em"), Typesetting:-mi("nops", italic = "true", font_style_name = "2D Input", mathvariant = "italic"), Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mfenced(Typesetting:-mrow(Typesetting:-mi("indx", italic = "true", font_style_name = "2D Input", mathvariant = "italic")), font_style_name = "2D Input", mathvariant = "normal", open = "[", close = "]")), font_style_name = "2D Input", mathvariant = "normal")), font_style_name = "2D Input", mathvariant = "normal"), Typesetting:-mo(";", font_style_name = "2D Input", mathvariant = "normal", fence = "false", separator = "true", stretchy = "false", symmetric = "false", largeop = "false", movablelimits = "false", accent = "false", lspace = "0.0em", rspace = "0.2777778em"))

Error, invalid input: subs received res[indx[1]](0), which is not valid for its 1st argument

 

``

``


 

Download mar.mw

 

I would like to solve the following differential equation with a relatively complicated function that is best declared.

myfun := proc (x::float)

local output;

output := 4*x^2;

end proc;


de := diff(y(x), x)+myfun(x)*y(x) = 0.;

However, this gives the following message:

Error, invalid input: myfun expects its 1st argument, x, to be of type float, but received x

Any suggestions?

 

 

i am interested to numerically solve the 3 non-linear coupled ODE's in the 3 different intervals of rho(define in attached file) for the different corresponding parameters alpha and beta at i=0..2.

density_interval_solution.mw 

Hello,

when trying to solve my equation I always get this error-message:

Error, (in DEtools/convertsys) invalid input: degree expects 1 or 2 arguments, but received 3

To solve, I use this one:

Anfangsbed := phi(0) = 0,  D(phi)(0) = 10;

Einst :=             range = 0..10,            #Integrationsgrenzen
                     relerr = 1e-3,            #Toleranz zur Bestimmung der Integrationsschrittweite
                     optimize = true,          #Optimierung der DGL
                     maxfun = 0,               #Anzahl der Integrationsschritte -- 0 = keine Obergrenze
                     output = operator,        #Lösungsfunktionausgabe: damit Definition als Funktion möglich 
                     stiff = true:

 

Lösung_Bewgl := dsolve({Bewegungsgl_mit_Para, Anfangsbed}, numeric, Einst);

The equation to solve is this one: http://imgur.com/a/SFxI8

What am I doing wrong?

Edit:

This is the worksheet, problem is the last point.

WS.mw

Hey there!

 

this is the formula:

diff(ca(t), t) = -3.600000000*10^20*exp(-15098.13790/(340-20*ca(t)))*ca(t), ca(0) = 2

I can easily plot it by solving DE numerically, however I can't seem to find a way to determine what 't' is at ca(t)=0.2

 

thank you so much in advance!

Kind regards, 

Gerard 

Download 2222222222222222222.mw

 

> restart; 
> A[0] := 10^(-3); a := 10^5;
> sys := diff(R(theta), theta) = A[0]*exp(2*mu(theta))*sin(theta)/(2*a), R(theta) = 2*exp(-2*mu(theta))*(1-(diff(mu(theta), `$`(theta, 2)))-cot(theta)*(diff(mu(theta), theta)));
> cond := R(0) = 10^(-5), mu(0) = 118.92, (D(mu))(0) = 0;
> F := dsolve({cond, sys}, [R(theta), mu(theta)], numeric);
> with(plots);
> odeplot(F, [theta, R(theta)], 0 .. 3.14, color = black, thickness = 3, linestyle = 4)
> odeplot(F, [theta, mu(theta)], 0 .. 3.14, color = blue, thickness = 3, linestyle = 1)

After last two lines maple writes:

Warning, cannot evaluate the solution past the initial point, problem may be complex, initially singular or improperly set up

And gives me empty plots. I can't figure out where an error can be. Some things I noticed:

Maple doesn't calculate the system before and after zero. If I change the range from 0..3.14 to -10..10 or to 0.00001..0.00001, it gives me 2 errors for 1 plot.

Also if I change the condition mu(0) = 118.92 to mu(0) = 1 or mu(0) = 50 or mu(0) = 80, it works. After ~80 it gives an error. I can't imagine where could appear a division by 0 or some other mistake.

Hey, i'm trying do demonstrate that a nonlinear system has a semistable limit cycle but i get a warning at the plot command saying "Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct" and i dont understand it. So i wonder if someone here could help me? 

 

restart; with(PDEtools); with(plots);
eq1 := diff(x(t), t) = x(t)*(x(t)^2+y(t)^2-1)^2-y(t);
                                             2       
           d              /    2       2    \        
          --- x(t) = x(t) \x(t)  + y(t)  - 1/  - y(t)
           dt                                        
eq2 := diff(y(t), t) = y(t)*(x(t)^2+y(t)^2-1)^2+x(t);
                                             2       
           d              /    2       2    \        
          --- y(t) = y(t) \x(t)  + y(t)  - 1/  + x(t)
           dt                                        
tr := {x(t) = r(t)*cos(theta(t)), y(t) = r(t)*sin(theta(t))};
     {x(t) = r(t) cos(theta(t)), y(t) = r(t) sin(theta(t))}
eq1b := dchange(tr, x(t)*eq1+y(t)*eq2, [r(t), theta(t)], simplify);
              / d      \       2 /        4         2\
         r(t) |--- r(t)| = r(t)  \1 + r(t)  - 2 r(t) /
              \ dt     /                              
eq1b := expand(eq1b/r(t));
                d                    5         3
               --- r(t) = r(t) + r(t)  - 2 r(t) 
                dt                              
eq2b := dchange(tr, y(t)*eq1-x(t)*eq2, [r(t), theta(t)], simplify);
                      2 / d          \        2
                 -r(t)  |--- theta(t)| = -r(t) 
                        \ dt         /         
eq2b := simplify(eq2b/(-r(t)^2));
                         d              
                        --- theta(t) = 1
                         dt             
sol1 := dsolve({eq1b, r(0) = r[0]}, r(t));
          /      /  /     2  \                 
          |      |  | r[0]   |          2     2
r(t) = exp|RootOf|ln|--------| (exp(_Z))  r[0] 
          \      \  \r[0] - 1/                 

                           2     2
   - ln(r[0] + 1) (exp(_Z))  r[0] 

       /             2\                                       
       |(exp(_Z) - 1) |          2     2            2        2
   - ln|--------------| (exp(_Z))  r[0]  + (exp(_Z))  _Z r[0] 
       \ exp(_Z) - 2  /                                       

                                /     2  \              
                2     2         | r[0]   |             2
   + 2 (exp(_Z))  r[0]  t - 2 ln|--------| exp(_Z) r[0] 
                                \r[0] - 1/              

                                2
   + 2 ln(r[0] + 1) exp(_Z) r[0] 

         /             2\                                   
         |(exp(_Z) - 1) |             2                    2
   + 2 ln|--------------| exp(_Z) r[0]  - 2 exp(_Z) _Z r[0] 
         \ exp(_Z) - 2  /                                   

                           /     2  \           
                   2       | r[0]   |          2
   - 4 exp(_Z) r[0]  t - ln|--------| (exp(_Z)) 
                           \r[0] - 1/           

                                 /             2\           
                           2     |(exp(_Z) - 1) |          2
   + ln(r[0] + 1) (exp(_Z))  + ln|--------------| (exp(_Z)) 
                                 \ exp(_Z) - 2  /           

                                          /     2  \        
              2                   2       | r[0]   |        
   - (exp(_Z))  _Z - 2 t (exp(_Z))  + 2 ln|--------| exp(_Z)
                                          \r[0] - 1/        

                                  /             2\        
                                  |(exp(_Z) - 1) |        
   - 2 ln(r[0] + 1) exp(_Z) - 2 ln|--------------| exp(_Z)
                                  \ exp(_Z) - 2  /        

              2                                    2            
   - (exp(_Z))  + 2 _Z exp(_Z) + 4 t exp(_Z) + r[0]  + 2 exp(_Z)

      \\    
      ||    
   - 1|| - 1
      //    
sol1 := simplify(sol1);
          /      /   /     2  \                
          |      |   | r[0]   |               2
r(t) = exp|RootOf|-ln|--------| exp(2 _Z) r[0] 
          \      \   \r[0] - 1/                

                                2
   + ln(r[0] + 1) exp(2 _Z) r[0] 

       /             2\                                     
       |(exp(_Z) - 1) |               2                    2
   + ln|--------------| exp(2 _Z) r[0]  - exp(2 _Z) _Z r[0] 
       \ exp(_Z) - 2  /                                     

                               /     2  \              
                     2         | r[0]   |             2
   - 2 exp(2 _Z) r[0]  t + 2 ln|--------| exp(_Z) r[0] 
                               \r[0] - 1/              

                                2
   - 2 ln(r[0] + 1) exp(_Z) r[0] 

         /             2\                                   
         |(exp(_Z) - 1) |             2                    2
   - 2 ln|--------------| exp(_Z) r[0]  + 2 exp(_Z) _Z r[0] 
         \ exp(_Z) - 2  /                                   

                           /     2  \          
                   2       | r[0]   |          
   + 4 exp(_Z) r[0]  t + ln|--------| exp(2 _Z)
                           \r[0] - 1/          

                                /             2\          
                                |(exp(_Z) - 1) |          
   - ln(r[0] + 1) exp(2 _Z) - ln|--------------| exp(2 _Z)
                                \ exp(_Z) - 2  /          

                                        /     2  \        
                                        | r[0]   |        
   + exp(2 _Z) _Z + 2 t exp(2 _Z) - 2 ln|--------| exp(_Z)
                                        \r[0] - 1/        

                                  /             2\        
                                  |(exp(_Z) - 1) |        
   + 2 ln(r[0] + 1) exp(_Z) + 2 ln|--------------| exp(_Z)
                                  \ exp(_Z) - 2  /        

                                                  2            
   + exp(2 _Z) - 2 _Z exp(_Z) - 4 t exp(_Z) - r[0]  - 2 exp(_Z)

      \\    
      ||    
   + 1|| - 1
      //    
sol2 := dsolve({eq2b, theta(0) = theta[0]}, theta(t));
                    theta(t) = t + theta[0]
theta[0] := (1/4)*Pi;
                              1   
                              - Pi
                              4   
plot1 := polarplot([subs(r[0] = .1, rhs(sol1)), rhs(sol2), t = 0 .. 10], color = red);
Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct
plot2 := polarplot([subs(r[0] = 2, rhs(sol1)), rhs(sol2), t = 0 .. 10], color = blue);
Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct
display({plot1, plot2}, scaling = constrained, tickmarks = [4, 3], view = [-2 .. 2, -2 .. 2]);

newbie here. When I give Maple 2016.2  a boundary value ODE with an eigenvalue in it, it returns the trivial solution. I was wondering if Maple supports finding non-trivial solution and also give the eigenvalue values associated with the non-trivial solution?

restart;
ode:=diff(y(x),x$2)+lambda*y(x)=0;
bc:=y(0)=0,y(L)=0:
assume(L>0,L,'real'):
sol:=dsolve({ode,bc},y(x));

The outtput is `y(x)=0`

In Mathematica, it gives both trivial and non-trivial solution:

Clear[L0, lam, x, y, r]
ode = y''[x] + lam y[x] == 0;
bc = {y[0] == 0, y[L0] == 0};
sol = Assuming[Element[L0, Reals] && L0 > 0, 
  DSolveValue[{ode, bc}, y[x], x]]

And the answer is

If Maple does not currently support this, any one knows if this will added to Maple 2017?

 

How to solve delay differential equation by method of steps in MAPLE software. 

 

Hi I am getting this message while soliving my first order non-linear initial value problem.

please share me your thoughts

ode := dsolve({diff(y(x), x)-2*(diff(y(x), x))^3 = -2*x+2, y(0) = 1}, type = numeric, range = 0 .. .24);
Error, (in DEtools/convertsys) unable to convert to an explicit first-order system

Abbas

 

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