Hi in trying to solve these coupled differential equations i get a weird error:

> t := diff(X(x), x) = -(1-6*R(x)^(1/2))^(1/2)*x*X(x)/(X(x)*x+R(x))^(1/2), diff(R(x), x) = (1-6*R(x)^(1/2))^(1/2)*x^2*X(x)/(X(x)*x+R(x))^(1/2);
                                        (1/2)         
                       /          (1/2)\              
           d           \1 - 6 R(x)     /      x X(x)  
          --- X(x) = - -----------------------------, 

I am trying to evalute a double integral symbolically using Maple 15.  I have gotten it to work when some of the parameters are specific numbers, but it won't work if I use variables, even if I assume sufficient conditions on them for the integral to make sense.  I have tried to use AllSolutions but it didn't work.  Breaking it down into steps isn't working either. 

I am working on a file on a remote server and I don't think I can upload it here. ...

code for this with finite difference?

F''+f*F'-F^2-F=0

F=f'

F'(0)=0 , F(1)=1 , f(0)=0 , f(1)=0

tanx

The school computer labs use Maple 15. As it is a considerable drive for me to come in and use the lab during the hours I am not on campus, I picked up Maple 16. This has worked fine for me until today. I am trying to use the "polarplot" command to plot two equations r=8*cos(3θ) and r=4-2.5cos(θ). Doing so on the computer lab Maple 15 plots fine. When I do so on Maple 16 on my computer I get something different. If I switch the order of the equations on 16 I get...

I have a set of diffferential equations: 

> U := diff(X(x), x) = -10*(1-5*T(x)^2)^(1/2)*x*X(x)/(X(x)*x+R(x)), diff(R(x), x) = 10*(1-5*T(x)^2)^(1/2)*x^2*X(x)/(X(x)*x+R(x));
                                       (1/2)         
                          /          2\              
           d           10 \1 - 5 T(x) /      x X(x)  
          --- X(x) = - ----------------------------, 
           dx                 X(x) x + R(x)          

I dont know what to do any further...

I have some function containing HeunG as a function

it is of the following form

f(k)=argument(functions containing HeunG) - ln(2)*k

now plotting this works...

But when differentiating with respect to k and then plotting it gives me the following message:

Warning, expecting only range variable k in expression (I*((1/2)^(1/2*I*k))^2*HeunG(3,-9/2+3/4*I*k-3/4*k^2,-1+1/2*I*k,-1/2+1/2*I*k,1/2,1+I*k,1/2...

Hi, i´m trying to understand how does maplesim simulate a model with differential equatyions and on maplesim help i found this:

"Numeric Integration and Event Handling

During numeric solving (or "integration"), inequality conditions that are part of the model
are monitored and an event is triggered when one or more of these conditions change.
Whenever such an event is encountered, the numeric solver is stopped and the simulation

Hi,

I have two differential equations describing a solar sail in 2D.

One is my radial direction and one is the tangential direction.

I have plotted r(t) and theta(t) but I want r(theta) so I have assigned my two differential equations and initial conditions, have my two plots for r and theta in terms of t and then I have used the following command to plot in polar coordinates:

Hi guys,

let's say that we have an ugly, massive long expression with high power products of variables for example this:

and we want to reduce the powers of these variables using these rules:

To Whom it May Concern:

I have a 3D array, P, with dimension P:=array(1..6,1..6,1..5). I would like to extract each 2D array from the 3D array and declare them as matrices. Additionally, I would like to store the sequence of matrices is a 1D array. I tried the following, but it did not work:

P:=array(1..6,1..6,1..5):

L:= matrix(1..6,1..6):

V:=array(1..5):

for l to 5 do: for i to 6 do: for j to 6 do: L[i,j] := P[i,j,l]: od: od: V[l]:=L: od:

Thx that has been helpful, would it be possible to sub these solutions F(t) into into another equation and then plot that as well? 

The other equation is: n = 10*((1/100)*modulus(diff(F(t), t))^2+modulus(diff(F(t), t)))-1/2

but i don't know if it is possible to code for that, thanks guys when we learned maple it was a pathetic 2week course and i have been struggling.

Hi

Maple wont do anything when i try to solve: DEsolve(diff(X(x), x, x)+(1.6+4*EllipticF(x, 2)^2)*X(x))

any help would be appreciated, as i need to plot the solution but I can't solve it, also the elliptic function is was aiming for was cn^2(x,2) im not sure if this is the version that i have included and so help would be appreciated.

I'm not sure this topic has ever come up.  I cannot find a way to output strikethrough characters.  Underline and subscript will get you strikethrough characters.  Is there a way to produce strikethrough output?

Hi all, I'm hopeful someone can help you with this issue I am having in implementing a Maple procedure. I use to have a strong knowledge of the programme, but haven't used Maple in a couple of years and I appear to be more rusty than I recall, I keep hitting dead ends with multiple assignments, missing arguements and so forth, so I was hoping someone can help me smooth the edges!

The problem is as follows:

q1'' - f1(q1,q2) = - q1 / (q1^2 + q2^2) ^ (3/2)

I wrote down a covariance matrix through the following command:

 A := Matrix([[a, b], [b, c]], shape = symmetric, attributes = [positive_definite]);

and then I computed the Cholesky decomposition of this matrix using afterwards the command simplify as well

B := LUDecomposition(A, method = Cholesky)

C:=simplify(%)

What I obtained is this matrix

Matrix(2, 2, {(1, 1) = sqrt(a), (1, 2) = 0, (2, 1...