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:

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?

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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...

Hi I have the differential equations:

X := diff(F(t), t$2)+(10+8*sin(m*t)/(m*t))*F(t) = 0

I know that if it were X := diff(F(t), t$2)+(W)*F(t) = 0, where W was a constant, then the solution would be the standard WKB sol, but with a time varying function in front this solution is no longer valid.

I know this can be done and would like some help in plotting F(t) against t and i sholud look an oscialltig curve where when sin(mt)=0 it...

Hi,

I'm new in Maple and i've a project to do. I've to find at what time is 90% of the steady-state concentration of C achieved. And the eq is 

z'=k(1/2-z)(1/3-z), where k=0.3. 

So i had worked in Mathematica before and i know that it would look something like that in there: 

eqn1 = 0 == k (1/2 - z[t]) (1/3 - z[t])

DSolve[Evaluate[{eqn1}], z[t]].

But i have no idea how to find this 90%. I hope that someone will...

People:

I wrote a Maple 15 worksheet containing a function that calls two other functions defined earlier in the worksheet.  The main function didn't work, so I replaced one of the functions that was called, by cut-and-pasting its definition into the main function.  This is obviously inconvenient because I want to alter the function that I cut-and -pasted and whenever I do it I will have to cut-and-paste again.  It also detracts from the...

Dear all, I am new here, so I am sorry in advance if I make some mistakes. The problem here is how to transform

system of 2 differential equations 4th order to the system of 4 diff equations second order, or how to reduce system of 2 equations 4th order on two equations second order with vanishing solutions which I choose because they are big. Here is example

I'm trying to use solve to find out if a system of equalities and inequalities has any solution or not, but maple 15 seems to be giving phantom solutions.  A simple example is the following:

  solve({ a + b = 1, a > 0, b > 1, c > 0 }, {a,b,c});

It gives the output

I have a set of equations

Hello,

I'm going to ask an question which I think it has an easy answer. However, I can't figure it out.

I wonder why f:x->sin(x)/x is not considered as a function. When I type "type(f(x),'function')", Maple says it's false, even though I don't know why. I'm asking this because I'm making a procedure in which one of the parametres is a function and when I type

aprox:=proc(fn::function,x::realcons,iteracions::integer)