Dear Maple users

We are using Maple at our school. Usually activation with the Activation code works well if the computer has a good connection to the Internet. Our data instructor have however experienced a problem with two computers he cannot seem to solve. He is not able to activate Maple 16 on those computers. After a failure in activation he even reset the license.dat file. Maybe someone have an idea to how we can get those computers activated and what the problem...

I need the button that will change the content (list) of a ListBox. When I create such Maplet, ListBox behaves very strange! The ListBox sometimes shows the list after the button click, but sometimes the list disappears. 

The code below reproduces this strange behavior. Just click the button several times.

with(Maplets[Elements]):

getObjects := proc()
local testList;
use Maplets:-Tools in
testList := ["YAHOO", "YAHOO", "YAHOO", "YAHOO", "YAHOO", "YAHOO"];...

hello every body

how can i solve this equation with respect to z

a, b are constants

3a(1+z)^2=2(a(1+z)^3+b)^(1/2)

Dear experts, I have problems about "subs", see below

> restart:

> assume(A>0): interface(showassumed=0):
> f:= A^2-2*sqrt(A^2+1)+1;

Now I want to replace A^2+1 to M^2, so idealy, what I want to see is

M^2 + M

When I do:

> f2:= subs(A^2+1 = M^2,  f);

Maple shows 

A^2-2*sqrt(M^2)+1

Maple cannot replace A^2+1

I need to define a tridiagonal matrix in maple in such a way that

[b(1) a(1) . . . . .      . . . . . . .  . 0]

[a(2) b(2) a(2) 0 0 .  . . . . . . . . .0]

[0  a(3) b(3) a(3) 0 0 0 .     . . . .0]

[0 0     a(4)  b(4) a(4) 0 0  .       . 0]

[0 . . . . . . . . . . . . . . . . . . . . .  . .]

[. . . . . . . . .a(m-1) b(m-1) a(m-1)] 

I have a very large system of rather long equations.   I need to find a way to have maple recognise if two equations within the system are the same.  I've been attempting to do this by adding each of them to the same set.  Maple automatically eliminates two identical entries in a set, so this works quite well for, say, x+y=0 and y+x=0 - maple knows these are the same and deletes one from the set automatically.  However it does not recognise that x+y=0 is the same as 2x + 2y = 0.

I have been told that dsolve solves a second order differential equation by making two coupled first order equations.

Could someone please explain to me the reason that this is done?

The verticies are of a 4x4 square, 16 in total.  You may cross a verticie only once, and you can move horizontally, vertically and diagonally.

Lets label the verticals  a,b,c,d and from bottom to top 1,2,3,4.  How would you find all the routes with a travel length of 6?

Hello all,

I have the state-space form of a dynamics sytem:

X_dot = AX+B.U

Y= C X,

The initial conditions of the outputs (Y0) are also given.

A is 7x7 known matrix,

C is 14x7 known matrix,

B = 0;

The problem is that it's too long to write down every equations (14+7 eqns) and variables in "dsolve" function

Would you please show me the shorter way to solve a very large state-space system?

I really appreciate your help.

Hi all,

I have the following equation: A.X = Y

A is a 14x7 known matrix, Y is a 14x1 known matrix, and X is a 7x1 unknown matrix Would you please how to find the solution X of this equation in Maple.

Thank you so much,

STH

PS: I attached matrices A and Y in this post
A.txt
Y.txt

I have a list L. In geom3d, I want to write all tangent of plane of the sphere S from L. But I don't know. I only write one point . I tried 

> restart:

with(geom3d):

L:=[[-5, -5, 8], [-5, -1, 10], [-5, 3, 10], [-5, 7, 8], [-5, 8, -5], [-5, 8, 7], [-5, 10, -1], [-5, 10, 3], [-1, -5, 10], [-1, 7, 10], [-1, 10, -5], [-1, 10, 7...

well am confuse because of my scheme which is 

(1-3r)U[i-1,j+1] +2(2-3r)U[i,j+1] +(1-3r)U[i+1,j+1]= (1+3r)U[i-1,j] +2(2+3r)U[i,j] +(1+3r)U[i+1,j]

now problem here is coefficients with U.. they are not similar on both sides so please can u let me know code about this...now here how can i generate matrix of oder n x n using this scheme...thanks

Dear Maple Users,

I do need to find the intersection of two surfaces which defined by two equations eq1 and eq2, (see attached file).

There was similar question on the MP: 
http://www.mapleprimes.com/questions/127821-How-To-Plot-The-Intersection-Of-Three-Surfaces

, but that doesn't work in my case. And I can't understand why....

Hello everyone,

I am trying to execute a procedure but its not giving me the desired output.

Please have a look.

Ad_proc.mw

Thanks

Hi,

Quite often, the result Maple gives involves exponents.

For example:

0.26/0!*e^-0.26.

When I use "evalf", "simplify", or right-click and select "approximate," I always obtain a fraction with e^13/50. How an I get a numerical approximation!

Thanks!