I don't understand why 'expand(x+y)^18' the smart popup work, but with 'expand(x+y)^19'  (or more then 19) i have no smart popups!

Any idea?

Thank you all

Hi 

I am a Matlab user and just started using maple because I need more precision for my calculations. I failed to make Matlab interface work, therefore, I am writing my codes from the begining. And I am having a problem with a nested for loop.

The thing that I am trying to make is (in Matlab)

for j=1:N;
    for i=mod(j-1,2):2:j;
D(i+1,j+1)=2*j;
    end
end

In maple I tried something like

Hi Maple Community!!

Using dsolve, Mathieu 15 gives me the following solutions:

Given that I have specific values for b, e and g. How can I plot x(t...

I have another differential equations that I can't find the integral of its solution by applying above 2 methods. Maple runs more than 10 mins without results. These equations are attached in this comment.

I really appreciate all your help.

DAEs_solver.mw

I have a matrix of order 14 with whose entries being variables about u_1 to u_12. I want to get its determinant, but it return no results. It explains that it is too big for maple to deal with. So I wonder how to deal with such kind of this problem?

Thank you very much for kind attention!

I am trying to solve a system of 4 odes by using the following program:

with(plots):

Pr:=6.2:Ha:=10^(-12):Nt:=0.1:Nb:=0.1:Nr:=0.1:Gr:=0.1:Ec:=0.1:Rb:=0.1:Lb:=1:Pe:=1:tw:=0.2:Le:=5:

fcns:={f(y),T(y),S(y),G(y)}:

sys:=diff(f(y),y$3)+f(y)*diff(f(y),y$2)-diff(f(y),y)*diff(f(y),y)-Ha*diff(f(y),y)+Gr*(T(y)-Nr*S(y)-Rb*G(y))=0,

diff(T(y),y$2)+Pr*f(y)*diff(T(y),y)+Nb*diff(S(y),y)*diff(T(y),y)+Nt*diff(T(y),y$2)*diff(T(y),y$2)+Pr*Ec*(diff(f(y...

Hello

I am trying to find the maximum of values in dsolve. In part 1 we solve the equation. In part 2 we do a doolop to know the values for specific time such as t=2. In part 3 we try to give this values names such as y[i] then to find the maximum of these values but it did not work for the maximum it gave y6 instead of the value.

Also, is it possible to save all values from dsolve  to a file the call it to find the maximum at each t?

Hi! I have a matrix A where the entries

satisfy the conditions in eq1. I set A equal

to the general

4x4 matrix X and convert to a set so that I can 

solve the system of equations for the variables

in A (i.e. solve for a,b,c,d, s,t,r,l). However,

in my program below, I get "res:= "

when the program finishes. Why isn't it

giving me any output? Thanks!

Please help me in this integration. It does not work.  

restart;with(LinearAlgebra); with(linalg);

Q := x->0.5*erfc(x/sqrt(2));

rho:=0.25;sigma := 0.3;

m1 := sigma*sigma*Matrix(3, 3, [1, rho, rho^2, rho, 1, rho, rho^2, rho, 1]);

SNR := 15; mu := evalf(10^(.1*SNR));

 a := Matrix(1, 3, [(ln(y/mu)+4*sigma^2)^2, (ln(y1/mu)+4*sigma^2)^2,

 (ln(y2/mu)+4*sigma^2)^2]);

having its diameter equal to three and its number of vertices equal to 32? Is it possible to find the one with Maple? The simpleminded approach
>with(GraphTheory):
>with(RandomGraphs):
> G := RandomRegularGraph(32, 4);
> Diameter(G);
produces 4 or 5.
What I know is http://www-ma4.upc.es/~comellas/delta-d/desc_g/desc_g3.html ( the second graph).

 In the following root finding code, the wn[1] is calculated as [] although it is within the specified range. would you please tell me why?

integrate ∫dx/√((x^2+1)(ln(x^2+√(x^2+1)))

In calculus of variations one may have the integrand of a functional F = sqrt(1+(y'(x))^2)

How do I get Maple to evaluate ∂F/∂y' ? (Maple doesn't recognise y' like Mathematica does)

( The answer is, of course, y'y''/sqrt(1+(y'(x))^2) )

hi,

i have an exercise ,i have to do for sunday:

a program on maple 13 of o numerical solution of heat equation for  semi-infinite rod where a finite quantity of heat is injected into the left end in the form of pulse instant

please i need your help.

I know

convert(sin(x),expln)

can convert sin(x) to expression which has "exp"

but how to produce the inverse operation?