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?

Maple people:

I just installed Maple 16 on my home PC.  I prefer using Classic Worksheet Maple, so that I can actually tell what I have typed, and what I type appears in red typewriter font.  I also would like matching parentheses to blink when I enter stuff so I enter the right number of parentheses.  Maple works this way on my office PC, but I can't get it to work this way at home.  I could simply use regular Maple 16 (not Classic Worksheet...

Dear all,

need to take data(a,u) from eq1 and plug it in eq2

eq1 is:

eq2 is:

Then need to plot data (a,v)

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

I did that:

points:=seq([a,evalf(solve((alpha+(l+alpha)*u+alpha*k*u^2)*a=u*(alpha+(l+alpha)*u+alpha*k*u^2...

Hi,

I'm trying to write a function in an 'n' dimensional vector such that I can call upon this function in a loop to define hessian matrices, or simply evaluate the function value for a given input. Here's an example:

F(x,y,z)= 6*x^2 + 3x*y^2 - 1.5*z^3

which is a function in 3 dimensions with x,y,z representing the 3 components of a design vector.

I want to be able to call upon this function in a loop such as: