Hi

worksheet output doesnt display the eigenvalues of a 19X19 matrix. Just gives in the form Root of(...). when datatype is indicated as anything other than complex(sflot) it gives error "unable to store". solution is required in compact mathematical expression form (may involve square roots etc). Please help.

Thanks

When I try "touch and drag" in Maple documents, the documentation for example, I end up selecting text instead of scrolling. Unfortunately the alternatives for scrolling are a) the scrollbar, b) page-up/down or c) moving the cursor. Each of those alternatives is about 2.5311 orders of magnitude more inconvenient than touch&drag.

Does anybody know if its possible to get Maple (18) to scroll instead of select text when I touch the screen?

Hello,

• Is there a simple way to find the domain for the real solutions of f(x)?

• And is there a way to let maple get the part of f(x) with the sqrt?
   (not by typing it by hand as I dit below)

• Is there a way to write the summary of the found domains in one line?

Thanks for your help. 





restart:
# How to find the Domain for real solutions for x?
f(x):=(x-1+sqrt(x^2-3*x+2))/(x-1);
discont_for_x=discont(f(x),x);
# x<>+1 (because the de denom=0 is not allowed)
denom(f(x))=0;
x={solve(denom(f(x))=0,x)};
# x<=1 union  2<=x (because the part under the sqrt must be >=0 to give Real solutions)
sqrt(x^2-3*x+2);
0<=x^2-3*x+2;
x=solve(0<=x^2-3*x+2,x);

I'm trying to plot the direction field of the second order differential equation x''=x'-cos(x) using dfieldplot: 

> with(DEtools); with(plots);
> f1 := (x, y) options operator, arrow; diff(x(t), t)-cos(x(t)) end proc;
/ d \
(x, y) -> |--- x(t)| - cos(x(t))
\ dt /
> dfieldplot([diff(x(t), t) = y(t), diff(y(t), t) = f1(x(t), y(t))], [x(t), y(t)], t = -2 .. 2, x = -2 .. 2, y = -2 .. 2);
Error, (in DEtools/dfieldplot) cannot produce plot, non-autonomous DE(s) require initial conditions.
>

The error I'm getting says I need initial conditions, but I wasn't provided with any. Is there another way to plot this? Sorry if this is dumb question, but I've only ever plotted first order equations.

I need to maximize two multivariate objective functions (f(x1,y1,z1,t1) and g(x2,y2,z2,t2)) with inequality and nonnegativity constraints (x1, x2>0 and y1, z1, t1, y2, z2, t2 >=0). I am looking for parametric not numerical solutions.

What is the best way to find the solution to such a problem using maple?

When trying to solve a set of partial differential equations, I always get the following error. I don't know what it means. Can somebody help me?

write down the mapple procedure that finds the shape operator plus
gauss and primative curvatores and determines the surface characteristic
of a parametically given surface

best regards, ty

I have a question regarding maple reader.

It seems like in maple reader, one cannot interact with the output of the Explore function.... which mean I am forced to make my own component if I want to creat application for my co-worker to use..this is some what annoying.  Is there another way around?

please open the attached file in maple player and you will see the output created by Explore gives error message.  mapleplayer_test.mw

Download mapleplayer_test.mw

.  

intsolve(int(f1(u)*(x-y), u = a .. b) = (12)*cos(x)+5*x^2-12, f1(x));I try to resolve the integral equation but i received all the time the followinf message error 

Error, (in intsolve) invalid input: rhs received {f1(x) = ?}, which is not valid for its 1st argument, expr
I try to use different form but i do not how to resolve the help center do not help to much.

I preciate any help thanks

i cant find the error the program is saying i have 

> L := -1.576674; MU := 0; DE13 := {D(y)*t = -x(t)*(1-2*x(t)*x(t))+MU*y(t)*(x(t)*x(t)-3*y(t)*y(t)-L), (D(x))(t) = y(t)*(1-y(t)*y(t))+MU*y(t)*(x(t)*x(t)-3*y(t)*y(t)-L)}; DEplot(DE13, [x(t), y(t)], t = -20 .. 20, [[x(0) = 0.1e-1, y(0) = .99], [x(0) = 0.5e-1, y(0) = .95], [x(0) = .1, y(0) = .9], [x(0) = 0.4e-1, y(0) = .96]], stepsize = 0.1e-2, scene = [x(t), y(t)], title = "phaseplane plot", linecolor = black, thickness = 1, number = 1000);
 
Error, (in DEtools/DEplot/CheckInitial) too few initial conditions: [x(0) = 0.1e-1, y(0) = .99]

it might be hard to read but if someone could help me it would be very appreciated 

Hi

I need a temperature distribution inside a barrier during a heating process.
I will be appreciated for any help.

wz

Download heating.mw

restart:

Eq1:=1/r*diff(r*diff(w(r),r),r)-(cos(z1))^2*(w(r)+1)-DP;

dsolve({Eq1});

bcs:=D(w)(0)=0,w(r2)=A1;

dsolve({Eq1,bcs},w(r)):

where z1, Dp, r2, A1 are constants.

Dear all

Please I need your help to simplify by the coefficient a in this Matrix

I have The matrix A defined by  A:=Matrix(2,2, [[a,a],[3*a,4*a]]);

I want with maple transform A to  A:=a*Matrix(2,2, [[1,1],[3,4]]);

Thanks for your Help.

Dear all;

Please see only the last lines of this procedure,

1)I ask if this procedure give an output epsilon(x0,h). Really, I need your help. Thanks.

2) Can we plot epsilon(x0,h), versus h

> heun := proc (x0, h)

local x, y, i, N, k, f, ode, k1, k2, x1, x2, y1, y2;

f :=(x,y)-> 1/(1+cos(y)) ;

ode := diff(y(x), x) = f(x, y);

N := round((1/2)*x0/h);

y2 := Array(0 .. N);

x2 := Array(0 .. N);

y1 := Array(0 .. 2*N);

x1 := Array(0 .. 2*N);

x2[0] := 0; y2[0] := (1/4)*Pi;

for i from 0 to N-1 do

x1[2*i+2] := (2*i+2)*h;  k1[1] := f(x1[2*i], y1[2*i]); 

k1[2] := f(x1[2*i]+h, y1[2*i]+h*k1[1]);

y1[2*i+2] := y1[2*i]+(1/2)*h*(k1[1]+k1[2]);

x2[i+1] := (2*i+2)*h;

k2[1] := f(x2[i], y2[i]);

k2[2] := f(x2[i]+2*h, y2[i]+2*h*k2[1]);

y2[i+1] := y2[i]+h*(k2[1]+k2[2])

end do;

return firstresulat = evalf([seq([x2[i], y2[i]], i = 0 .. N)]);

return secondresulat =evalf([seq([x1[2*i], y1[2*i]], i = 0 .. N)]);

epsilon:=(x0,h)->add((firsttest[i][2]-secondtest[i][2])^2 , i=1..round(x0/(2*h))+1)

end proc;

how maple calculate exp(x) with e.g. 100000 decimal numbers

a divsion of the series x^k/k! with e.g. 1/25000!/25001 lasts longer than the exp(1.xx) calculation

is there a faster way to calculate exp(x) than with the x^k/k! series

thanks