Maple Questions and Posts

These are Posts and Questions associated with the product, Maple

The series to ode using 'series' option (if it exists) should always be series(...), i.e. with big O at end. but sometimes Maple forgets to add this. Here is an example

interface(version);

`Standard Worksheet Interface, Maple 2025.0, Linux, March 24 2025 Build ID 1909157`

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1862 and is the same as the version installed in this computer, created 2025, April 25, 10:33 hours Pacific Time.`

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 15 and is the same as the version installed in this computer, created April 27, 2025, 23:18 hours Eastern Time.`

restart;

ode:=diff(y(x),x)+y(x)=1+x;
IC:=y(0)=0;
sol:=dsolve([ode,IC],y(x),'series')

diff(y(x), x)+y(x) = 1+x

y(0) = 0

y(x) = x

lprint(sol); # notice solution is not series, it should be

y(x) = x

#above solution should be
y(x) = series(x+O(x^6),x,6)

y(x) = series(x+O(x^6),x,6)

#this example below is correct
ode:=diff(y(x),x)+y(x)=1+x;
IC:=y(0)=1;
sol:=dsolve([ode,IC],y(x),'series')

diff(y(x), x)+y(x) = 1+x

y(0) = 1

y(x) = series(1+(1/2)*x^2-(1/6)*x^3+(1/24)*x^4-(1/120)*x^5+O(x^6),x,6)

lprint(sol); #solution is series

y(x) = series(1+1/2*x^2-1/6*x^3+1/24*x^4-1/120*x^5+O(x^6),x,6)

 

 

Download bug_report_dsolve_series_april_28_2025.mw

Hello everyone,

I am creating this post to begin a thread where I will share a series of worksheets on important topics in Complex Analysis, written as part of my notes for my classes. Complex_Analysis_Notes.pdf

The planned sections include:

  • Section 1: Infinite Series

  • Section 2: Power Series

  • Section 3: The Radius of Convergence of a Power Series

  • Section 4: The Riemann Zeta Function and the Riemann Hypothesis

  • Section 5: The Prime Number Theorem

Each worksheet will include calculations, plots, and examples using Maple to illustrate key ideas.

I plan to upload one worksheet every week to keep a steady pace and allow time for discussion and feedback between posts.

I hope this thread will be helpful both for learning and for deeper exploration.
Feel free to comment, suggest improvements, or ask questions as I post the materials.

Thank you!

restart; interface(imaginaryunit = 'I'); z := I*(1/3); S_N := proc (n) options operator, arrow; sum(z^k, k = 0 .. n) end proc; limit(S_N(n), n = infinity); S_N(10); S_N(100); S_N(1000); with(plots); points := [seq([Re(evalf(S_N(n))), Im(evalf(S_N(n)))], n = 0 .. 50)]; pointplot(points, connect = true, symbol = solidcircle, symbolsize = 10, color = blue, labels = ["Re", "Im"])

proc (n) options operator, arrow; sum(z^k, k = 0 .. n) end proc

 

9/10+(3/10)*I

 

53144/59049+(5905/19683)*I

 

 

restart; interface(imaginaryunit = 'I'); z := I*(1/2); S_N := proc (n) options operator, arrow; sum(z^k, k = 0 .. n) end proc; limit(S_N(n), n = infinity); S_N(10); S_N(100); S_N(1000); with(plots); points := [seq([Re(evalf(S_N(n))), Im(evalf(S_N(n)))], n = 0 .. 50)]; pointplot(points, connect = true, symbol = solidcircle, symbolsize = 10, color = blue, labels = ["Re", "Im"])

proc (n) options operator, arrow; sum(z^k, k = 0 .. n) end proc

 

4/5+(2/5)*I

 

819/1024+(205/512)*I

 

 

NULL

restart; with(plots); interface(imaginaryunit = 'I'); S := proc (N) local n; sum(((1/2)*I)^n, n = 0 .. N) end proc; fullsum := sum(((1/2)*I)^n, n = 0 .. infinity); realpts := [seq([n, Re(S(n))], n = 0 .. 30)]; imagpts := [seq([n, Im(S(n))], n = 0 .. 30)]; limit(Re(S(n)), n = infinity); limit(Im(S(n)), n = infinity); horiz_reallimit := plot(4/5, k = 0 .. 30, color = black, linestyle = 2, thickness = 2); horiz_imaglimit := plot(2/5, k = 0 .. 30, color = black, linestyle = 2, thickness = 2); plots[display]([pointplot(realpts, symbol = solidcircle, style = pointline, color = blue, labels = ["n", "Value"], legend = "Real Part"), pointplot(imagpts, symbol = solidbox, style = pointline, color = red, labels = ["n", "Value"], legend = "Imaginary Part"), horiz_reallimit, horiz_imaglimit], axes = boxed, labels = ["n", "Partial Sum Value"])

4/5+(2/5)*I

 

4/5

 

2/5

 

 

restart; with(plots); interface(imaginaryunit = 'I'); H := proc (N) local n; sum(1/n, n = 1 .. N) end proc; limit(H(n), n = infinity); limit(Re(H(n)), n = infinity); limit(Im(H(n)), n = infinity); harmonic_pts := [seq([n, H(n)], n = 1 .. 100)]; harmonic_plot := pointplot(harmonic_pts, symbol = solidcircle, style = pointline, color = blue, labels = ["n", "Partial Sum Value"], axes = boxed)

infinity

 

infinity

 

0

 

 

restart; with(plots); interface(imaginaryunit = 'I'); S := proc (N) local n; sum(I^k/k, k = 1 .. N) end proc; realpts := [seq([n, Re(S(n))], n = 1 .. 100)]; imagpts := [seq([n, Im(S(n))], n = 1 .. 100)]; complex_pts := [seq([Re(S(n)), Im(S(n))], n = 1 .. 100)]; S_infinite := sum(I^k/k, k = 1 .. infinity); Re(S_infinite); Im(S_infinite); horiz_reallimit := plot(-(1/2)*ln(2), k = 0 .. 100, color = black, linestyle = 2, thickness = 2); horiz_imaglimit := plot((1/4)*Pi, k = 0 .. 100, color = black, linestyle = 2, thickness = 2); real_plot := pointplot(realpts, symbol = solidcircle, style = pointline, color = blue, labels = ["n", "Partial Sum Value"], axes = boxed, legend = "Real Part"); imag_plot := pointplot(imagpts, symbol = solidbox, style = pointline, color = red, labels = ["n", "Partial Sum Value"], axes = boxed, legend = "Imaginary Part"); plots[display]([real_plot, horiz_reallimit, imag_plot, horiz_imaglimit]); plots[pointplot](complex_pts, symbol = solidcircle, style = pointline, color = blue, axes = boxed, labels = ["Re", "Im"])

-(1/2)*ln(2)+((1/4)*I)*Pi

 

-(1/2)*ln(2)

 

(1/4)*Pi

 

 

 

restart; with(plots); interface(imaginaryunit = 'I'); S := proc (N) local n; sum((-(2/3)*I)^n, n = 0 .. N) end proc; fullsum := sum((-2*I*(1/3))^n, n = 0 .. infinity); realpts := [seq([n, Re(S(n))], n = 0 .. 30)]; imagpts := [seq([n, Im(S(n))], n = 0 .. 30)]; limit(Re(S(n)), n = infinity); limit(Im(S(n)), n = infinity); horiz_reallimit := plot(9/13, k = 0 .. 30, color = black, linestyle = 2, thickness = 2); horiz_imaglimit := plot(-6/13, k = 0 .. 30, color = black, linestyle = 2, thickness = 2); plots[display]([pointplot(realpts, symbol = solidcircle, style = pointline, color = blue, labels = ["n", "Value"], legend = "Real Part"), pointplot(imagpts, symbol = solidbox, style = pointline, color = red, labels = ["n", "Value"], legend = "Imaginary Part"), horiz_reallimit, horiz_imaglimit], axes = boxed, labels = ["n", "Partial Sum Value"])

9/13-(6/13)*I

 

9/13

 

-6/13

 

 

restart; with(plots); interface(imaginaryunit = 'I'); S := proc (N) local n; sum((I*Pi)^n, n = 0 .. N) end proc; realpts := [seq([n, Re(S(n))], n = 0 .. 100)]; imagpts := [seq([n, Im(S(n))], n = 0 .. 100)]; complex_pts := [seq([Re(S(n)), Im(S(n))], n = 0 .. 100)]; limit(S(N), N = infinity); limit(Re(S(n)), n = infinity); limit(Im(S(n)), n = infinity); real_plot := pointplot(realpts, symbol = solidcircle, style = pointline, color = blue, labels = ["n", "Partial Sum (Real Part)"], title = "Real Part of Partial Sums of (Pi i)^n", axes = boxed); imag_plot := pointplot(imagpts, symbol = solidbox, style = pointline, color = red, labels = ["n", "Partial Sum (Imaginary Part)"], title = "Imaginary Part of Partial Sums of (Pi i)^n", axes = boxed); complex_plot := pointplot(complex_pts, symbol = solidcircle, style = pointline, color = blue, labels = ["Re", "Im"], title = "Partial Sums in Complex Plane (Pi i)^n", axes = boxed)

undefined

 

undefined

 

undefined

 

 

 

 

restart; with(plots); interface(imaginaryunit = 'I'); S := proc (N) local n; sum(2*I^k/k, k = 1 .. N) end proc; realpts := [seq([n, Re(S(n))], n = 1 .. 100)]; imagpts := [seq([n, Im(S(n))], n = 1 .. 100)]; complex_pts := [seq([Re(S(n)), Im(S(n))], n = 1 .. 100)]; S_infinite := sum(2*I^k/k, k = 1 .. infinity); Re(S_infinite); Im(S_infinite); horiz_reallimit := plot(-ln(2), k = 0 .. 100, color = black, linestyle = 2, thickness = 2); horiz_imaglimit := plot((1/2)*Pi, k = 0 .. 100, color = black, linestyle = 2, thickness = 2); real_plot := pointplot(realpts, symbol = solidcircle, style = pointline, color = blue, labels = ["n", "Partial Sum Value"], axes = boxed, legend = "Real Part"); imag_plot := pointplot(imagpts, symbol = solidbox, style = pointline, color = red, labels = ["n", "Partial Sum Value"], axes = boxed, legend = "Imaginary Part"); plots[display]([real_plot, horiz_reallimit, imag_plot, horiz_imaglimit]); plots[pointplot](complex_pts, symbol = solidcircle, style = pointline, color = blue, axes = boxed, labels = ["Re", "Im"])

-ln(2)+((1/2)*I)*Pi

 

-ln(2)

 

(1/2)*Pi

 

 

 

restart; with(plots); interface(imaginaryunit = 'I'); S := proc (N) local n; add(exp(Pi*I*n)/n, n = 1 .. N) end proc; realpts := [seq([n, Re(S(n))], n = 1 .. 100)]; imagpts := [seq([n, Im(S(n))], n = 1 .. 100)]; complex_pts := [seq([Re(S(n)), Im(S(n))], n = 1 .. 100)]; S_infinite := sum(exp(Pi*I*n)/n, n = 1 .. infinity); limit_Re := Re(S_infinite); limit_Im := Im(S_infinite); limit_Re; limit_Im; real_plot := pointplot(realpts, symbol = solidcircle, style = pointline, color = blue, labels = ["n", "Partial Sum Value"], title = "Real Part of Partial Sums", axes = boxed); imag_plot := pointplot(imagpts, symbol = solidbox, style = pointline, color = red, labels = ["n", "Partial Sum Value"], title = "Imaginary Part of Partial Sums", axes = boxed); complex_plot := pointplot(complex_pts, symbol = solidcircle, style = pointline, color = blue, labels = ["Re", "Im"], title = "Partial Sums in Complex Plane", axes = boxed); plots[display]([real_plot, imag_plot]); plots[display](complex_plot)

-ln(2)

 

-ln(2)

 

0

 

-ln(2)

 

0

 

 

 

restart; with(plots); interface(imaginaryunit = 'I'); S := proc (N) local n; add(exp(2*Pi*I*n), n = 0 .. N) end proc; realpts := [seq([n, Re(S(n))], n = 0 .. 100)]; imagpts := [seq([n, Im(S(n))], n = 0 .. 100)]; complex_pts := [seq([Re(S(n)), Im(S(n))], n = 0 .. 100)]; S_infinite := sum(exp(2*Pi*I*n), n = 1 .. infinity); limit_Re := Re(S_infinite); limit_Im := Im(S_infinite); real_plot := pointplot(realpts, symbol = solidcircle, style = pointline, color = blue, labels = ["n", "Partial Sum Value"], title = "Real Part of Partial Sums", axes = boxed); imag_plot := pointplot(imagpts, symbol = solidbox, style = pointline, color = red, labels = ["n", "Partial Sum Value"], title = "Imaginary Part of Partial Sums", axes = boxed); complex_plot := pointplot(complex_pts, symbol = solidcircle, style = pointline, color = blue, labels = ["Re", "Im"], title = "Partial Sums in Complex Plane", axes = boxed); plots[display]([real_plot, imag_plot]); plots[display](complex_plot)

infinity

 

infinity

 

0

 

 

 
 

``

Download infinite_series.mw

In this work, I do not intend to expand all the variables across the monomials. Instead, I want to restrict the distribution to only the variables x,y,z,tx, y, z, tx,y,z,t, possibly raising them to appropriate powers as needed, until I obtain the desired solution and satisfy the conditions of my PDE tests. However, I am uncertain whether "monomial" is the correct term to use here.

S1.mw

trail-1.mw

These two expressions are the same, just pulled minus sign out

But look what happens when integrating them. the anti derivative of one is much more complicated than the other and contains complex numbers and logs. And no matter what I tried, I could not convert the complicated one to look same as the simpler result. Also could not verify the complicated one by back differentiating.

integrand_1:=x^2*(-arctan(x) + x)*exp(-arctan(x) + x)/(x^2 + 1);

x^2*(-arctan(x)+x)*exp(-arctan(x)+x)/(x^2+1)

integrand_2:=evala(integrand_1);

-x^2*(arctan(x)-x)*exp(-arctan(x)+x)/(x^2+1)

simplify(integrand_1 - integrand_2)

0

anti_1:=int(integrand_1,x);

(-arctan(x)+x)*exp(-arctan(x)+x)-exp(-arctan(x)+x)

anti_2:=int(integrand_2,x);

-(1-x+((1/2)*I)*ln(1-I*x)-((1/2)*I)*ln(1+x*I))*(1-I*x)^(-(1/2)*I)*(1+x*I)^((1/2)*I)*exp(x)

simplify(diff(anti_1,x)-integrand_1);

0

simplify(diff(anti_2,x)-integrand_2);

Error, (in simpl/simpl/ReIm/sum) too many levels of recursion

simplify(anti_1 - anti_2)

Error, (in simpl/simpl/ReIm/sum) too many levels of recursion

simplify(anti_2);

(1/2)*(I*ln(1+x*I)-I*ln(1-I*x)+2*x-2)*(1-I*x)^(-(1/2)*I)*(1+x*I)^((1/2)*I)*exp(x)

simplify(anti_2,ln);

(1/2)*(I*ln(1+x*I)-I*ln(1-I*x)+2*x-2)*(1-I*x)^(-(1/2)*I)*(1+x*I)^((1/2)*I)*exp(x)

 

 

Download int_strange_result_april_27_2025.mw

I would have expected same anti derivative to show.  To check, I used another software, and that one gave same anti-derivative for both integrands.

The questions I have: Why Maple gives such different result for same integrand? And how could one convert the one with the logs and complex numbers to the first one?

Maple 2025

Dear all 
I have a double integral, i want to compute this integral and verify if the pproposed solution verify the proposed equation or not. 
I can modify the right hand side of my equation or the exact solution, so that my equation has an exact solution with simple form of right hand side. 

exact_solution.mw

Thank you for your help 

 I am writing notes on complex analysis, I need to use figures of contour paths to integrate on them, i want to create something like this

I tried to plot the contour for 
\oint_{|z|=2} \frac{1}{z^2+1}\,dz
I need to have connecting lines all around because the poles can not be isolated

with(plots); circle1 := plot([2*cos(t), 2*sin(t), t = 0 .. 2*Pi], color = blue, thickness = 2); circle2 := plot([(1/2)*cos(t), 1+(1/2)*sin(t), t = 0 .. 2*Pi], color = "Green", thickness = 2); circle3 := plot([(1/2)*cos(t), -1+(1/2)*sin(t), t = 0 .. 2*Pi], color = "Red", thickness = 2); sing1 := plottools[disk]([0, 1], 0.2e-1, color = white); sing2 := plottools[disk]([0, -1], 0.2e-1, color = white); label1 := textplot([.1, 1.1, "z = i"], font = [Arial, Bold, 12]); label2 := textplot([.1, -1.1, "z = -i"], font = [Arial, Bold, 12])

display(circle1, circle2, circle3, sing1, sing2, label1, label2, scaling = constrained, labels = ["Re", "Im"])

 
 

restart; f := proc (z) options operator, arrow; 1/(z^2+1) end proc; z := 2*exp(I*t); dz := diff(z, t); integrand := f(z)*dz; simplify(integrand); value(Int(integrand, t = 0 .. 2*Pi))

0

(1)

Download CIF.mw

Hello all,

After updating the Physics package I have this error :

Physics:-Version();
The "Physics Updates" version "1862" is installed in the

   directory C:\Users\jm\maple\toolbox\2025\Physics Updates but

   is not active. The active version of Physics is within the

   library C:/Users/jm/maple/toolbox/2025/Physics Updates/lib\Ph\

  ysics Updates.maple.

What am I supposed to do next?

Thanks a lot and kind regards to all,

Jean-Michel

FYI;

 

You might have to try the command more than one time to see the above crash. Here is the worksheet

restart;

interface(version);

`Standard Worksheet Interface, Maple 2025.0, Linux, March 24 2025 Build ID 1909157`

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1862 and is the same as the version installed in this computer, created 2025, April 25, 10:33 hours Pacific Time.`

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 13 and is the same as the version installed in this computer, created April 22, 2025, 15:14 hours Eastern Time.`

restart;

ode:=x^2-2*x*y(x)+5*y(x)^2 = (x^2+2*x*y(x)+y(x)^2)*diff(y(x),x);

x^2-2*x*y(x)+5*y(x)^2 = (x^2+2*x*y(x)+y(x)^2)*(diff(y(x), x))

sol:=y(x) = (-1/2*exp(RootOf(-exp(_Z)^2*ln(x*(exp(_Z)-2))+2*_C7*exp(_Z)^2+_Z*exp(_Z)^2+4*exp(_Z)*ln(x*(exp(_Z)-2))-8*_C7*exp(_Z)-4*exp(_Z)*_Z-2*exp(_Z)-4*ln(x*(exp(_Z)-2))+8*_C7+4*_Z+6))^2+3*exp(RootOf(-exp(_Z)^2*ln(x*(exp(_Z)-2))+2*_C7*exp(_Z)^2+_Z*exp(_Z)^2+4*exp(_Z)*ln(x*(exp(_Z)-2))-8*_C7*exp(_Z)-4*exp(_Z)*_Z-2*exp(_Z)-4*ln(x*(exp(_Z)-2))+8*_C7+4*_Z+6))-6+2*(exp(RootOf(-exp(_Z)^2*ln(x*(exp(_Z)-2))+2*_C7*exp(_Z)^2+_Z*exp(_Z)^2+4*exp(_Z)*ln(x*(exp(_Z)-2))-8*_C7*exp(_Z)-4*exp(_Z)*_Z-2*exp(_Z)-4*ln(x*(exp(_Z)-2))+8*_C7+4*_Z+6))^2-6*exp(RootOf(-exp(_Z)^2*ln(x*(exp(_Z)-2))+2*_C7*exp(_Z)^2+_Z*exp(_Z)^2+4*exp(_Z)*ln(x*(exp(_Z)-2))-8*_C7*exp(_Z)-4*exp(_Z)*_Z-2*exp(_Z)-4*ln(x*(exp(_Z)-2))+8*_C7+4*_Z+6))+9)^(1/2))/(1/2*exp(RootOf(-exp(_Z)^2*ln(x*(exp(_Z)-2))+2*_C7*exp(_Z)^2+_Z*exp(_Z)^2+4*exp(_Z)*ln(x*(exp(_Z)-2))-8*_C7*exp(_Z)-4*exp(_Z)*_Z-2*exp(_Z)-4*ln(x*(exp(_Z)-2))+8*_C7+4*_Z+6))^2-3*exp(RootOf(-exp(_Z)^2*ln(x*(exp(_Z)-2))+2*_C7*exp(_Z)^2+_Z*exp(_Z)^2+4*exp(_Z)*ln(x*(exp(_Z)-2))-8*_C7*exp(_Z)-4*exp(_Z)*_Z-2*exp(_Z)-4*ln(x*(exp(_Z)-2))+8*_C7+4*_Z+6)))*x:

odetest(sol,ode);

 

Download crash_maple_2025_april_27_2025.mw

Hopefully a fix could be found for this.

When generating a file to update parts of maple (for example constants) is it best to put it in an initialization file or make a library archive .mla?

I fail to see the logic of using short form symbols for the scientific constants and then not being able to use that short form.  One manually has to equate the two as I show below.  Anyone see a reason not to do that in the internal programming?  Just wondering. 

with(ScientificConstants):

GetConstant(M__Sun)             

One has to use the names associated with those short forms described by the command

GetConstant(mass_of_Sun)

I would much rather like to use MSun , so what one has to do is manually equate them

MSun:=mass_of_Sun:

GetConstant(MSun)

I have a list of candidate solutions. Some of them satisfy my PDE test (i.e., they make the PDE equal to zero), while others do not. How can I separate the solutions that satisfy the PDE from those that do not?

Trail-pdetest.mw

ABC is an equilateral triangle of side 3 units. The points P, Q lie on BC, CA re-
spectively and are such that AQ = CP = 2units. If the point R lies on AB produced

so that BR = 1unit, prove that P, Q, R are collinear.

How to modify the ND procedure to handle derivatives with respect to more than three independent variables for higher-dimensional PDEs, it is work for [x,t] i want  it work for [x,y,z,t] , 

restart

with(PDEtools)

with(LinearAlgebra)

NULL

with(SolveTools)

undeclare(prime)

`There is no more prime differentiation variable; all derivatives will be displayed as indexed functions`

(1)

alias(F=F(x, t), G=G(x, t))

F, G

(2)

with(PDEtools):
undeclare(prime):

`There is no more prime differentiation variable; all derivatives will be displayed as indexed functions`

(3)

ND := proc(F, G, U)
  local v, w, f, g, a:
  v := op(F):
  if v[1] in U then w := -v[1] else w := v[1] end if:
  if v[2] in U then w := w, -v[2] else w := w, v[2] end if:
  f := op(0, F):
  g := op(0, G):
  a := diff(f(w)*g(v), U);
  convert(subs([w]=~[v], a), diff)
end proc:

ND(F, G, [x]);
ND(F, G, [t]);

-(diff(F, x))*G+F*(diff(G, x))

 

-(diff(F, t))*G+F*(diff(G, t))

(4)

ND(F, F, [x]);
ND(F, F, [x, x]);

0

 

2*F*(diff(diff(F, x), x))-2*(diff(F, x))^2

(5)

ND(F, G, [x$3]);

-(diff(diff(diff(F, x), x), x))*G+3*(diff(diff(F, x), x))*(diff(G, x))-3*(diff(F, x))*(diff(diff(G, x), x))+F*(diff(diff(diff(G, x), x), x))

(6)

ND(F, F, [x$3, t]);

2*F*(diff(diff(diff(diff(F, t), x), x), x))-2*(diff(diff(diff(F, x), x), x))*(diff(F, t))-6*(diff(diff(diff(F, t), x), x))*(diff(F, x))+6*(diff(diff(F, x), x))*(diff(diff(F, t), x))

(7)

NULL

NULL

#if i collect P1+P1+...+P7 it must get equation 26 in paper so i want define the up proc to open but is not for (3+1) dimesnion,

P1 := 9*ND(F, F, [x, t])

18*F*(diff(diff(F, t), x))-18*(diff(F, x))*(diff(F, t))

(8)

NULL

P2 := -5*ND(F, F, [`$`(x, 3), y])

0

(9)

P3 := ND(F, F, [`$`(x, 6)])

2*F*(diff(diff(diff(diff(diff(diff(F, x), x), x), x), x), x))-12*(diff(diff(diff(diff(diff(F, x), x), x), x), x))*(diff(F, x))+30*(diff(diff(diff(diff(F, x), x), x), x))*(diff(diff(F, x), x))-20*(diff(diff(diff(F, x), x), x))^2

(10)

P4 := -5*ND(F, F, [`$`(y, 2)])

0

(11)

P5 := alpha*ND(F, F, [`$`(x, 2)])

alpha*(2*F*(diff(diff(F, x), x))-2*(diff(F, x))^2)

(12)

P6 := beta*ND(F, F, [x, y])

0

(13)

P7 := gamma*ND(F, F, [x, z])

0

(14)

Download define.mw

L. B. Johnson once said: “I may not know much, but I know chicken sh#t from chicken salad.” And the same goes for mathematical software,  Maple is a good chicken salad.

These two numbers can be used to factor two previously factored RSA Challenge numbers:

4492372899485266683229032112393311539091890452003150017722229708882931615085372733373343061967162688807713966063216561545461119244883848142568154156987418243095913219694108294875951005535802313105656690937568115044857082104972025


252470349467980886727391223577367145704558455488893488785280129051457755334632136343591527439288590916228345021218177497619016135424030834870037054353008183582467637830682000623550252325843511739294850378626625818394419012275747807

I'm curious to see if anyone can identify the numbers and do the factorization. If no one has been able to solve this, I will post the solution context at a future date. There exists some very interesting mathematics behind this question that goes beyond a simple recreational diversion.
 

I am very confused by the y-value of the rightmost point on the plot below.

restart

I'd like to find the values of x for which x^2/(10^(-8)-x) = 5*10^(-3).

So I ask Maple to solve this equation.

evalf(solve(x^2/(10^(-8)-x) = 5*10^(-3)))

-0.5000010000e-2, 0.10000e-7

(1)

Do these solutions work?

eval(x^2/(10^(-8)-x), x = 1.0000*10^(-8)) = Float(infinity) 

eval(x^2/(10^(-8)-x), x = -0.5000010000e-2) = 0.5000000000e-2 NULL

Suppose I define the function

f := proc (x) options operator, arrow; x^2/(1/100000000-x) end proc = proc (x) options operator, arrow; x^2/(1/100000000-x) end proc 

f(10^(-8))

Error, (in f) numeric exception: division by zero

 

f(.999999*10^(-8)) = 0.9999980000e-2NULL

f(.99999*10^(-8)) = 0.9999800001e-3NULL

Now, the function seems continuous between these two points

plot(f, .99999*10^(-8) .. .999999*10^(-8))

 

It is late, and perhaps I am just tired and not seeing things clearly. I expected the topmost point on the right to have a y-value of 0.00999998, ie almost 0.01.

I expected that the bottom leftmost point to be 0.0009999800001, ie almost 0.001, and it is.

And I thus expected to show that there must be some x for which we have f(x)=0.005, which if I am not mistaken is between the two numbers. After all, 0.999998e-2-0.5e-2 = 0.499998e-2NULL

0.5e-2-0.9999800001e-3 = 0.4000020000e-2NULL

what am i missing here?


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