I wrote a program in order to find coordinates orthocenter of the triangle. Please comment for me. This is my code:

restart;

with(geom3d);

point(A,1,-3,0);

point(B,-2,1,1);

point(C,3,1,2);

line(AB,[A,B],t);

line(BC,[B,C],t);

ab:=ParallelVector(AB); 

bc:=ParallelVector(BC);

eq1:=Equation(plane(P,[C,ab],[x,y,z]));

eq2:=Equation(plane(Q,[A,bc],[x,y,z]));

eq3:=Equation(plane(ABC,[A,B,C],[x,y,z]));

i just installed maple 15 in my macbook but i can't find classic worksheet, is it only for window?

How can I replace/substitute a combination of variables with a new variable?

For example, if ...

h:=(1+i)^2+(1+i)^3*A+(1+i)^4*B

I want to assign the value g:=1+i

so that h returns g^2+g^3*A+g^4*B

Do I have to change the 1+i to a name? or can it be done as it is?

I am learning about programming; I have this equation:

2*K2*alpha*t=ln[(A0+E(beta-1/2)/(A0-E(beta+1/2)

The values of t, E are a list of values.

and K2 alpha and beta are unknown but i dont know how to do for graph the part of ln vs time and fit it to a line.

i want to solve a complex number useing sharp 9900 for example : cosh (7+j19) ......

so tell me how to write a program for solve this ???? or tell me how to solve it by sharp 9900 ????

For next list of variables 

RVars:=[[''Rla'',''Rlb'',''Rsa'',''Rsb'',''RN''], [''GAL'',''GBL'',''GAS'',''GBS'',''GN'']];

(no double qoutes, 2 single quotes, of course)

want all of them to be redefinable with suffix option i.e. both of operators below

assign(m || (RVars[1,1]), 5);

assign( RVars[1,1], 5);

should be reentered without restart as many as wish. With 2nd form everything...

I wrote a program to find the coordinates of thecenter circle circumscribed triangle

I find the least value of the function h(x) = 1+2*cos(2*x)+3*cos(4*x)+4*cos(8*x). I did

h:=x->1+2*cos(2*x)+3*cos(4*x)+4*cos(8*x);

minimize(h(x),x=-Pi/12..5*Pi/12,location=true);

But i received 1/2-3^(1/2), {[{x = 5/12*Pi}, 1/2-3^(1/2)]}. This is wrong answer. This is shown by

plot(h(x),x=-Pi/12..5*Pi/12); 

can you explain me when i solve equation beta-t*beta=0 with condition beta<>0. I write command:
r :=solve(beta-t*beta, t, UseAssumptions), assuming beta <> 0
It works well. But it will be a problem when command is:
r :=solve(beta-t*beta, t, UseAssumptions), assuming beta <> 0, gamma<>0;
Error: Error, (in assuming) when calling 'assume'. Received: 'cannot assume on a constant object'.
thank you very much.

Hello,

I need to verify some terms in an equation which would involve the application of chain rule. I have A:=f(x,y), x:=g(t,s) and y:=h(t,s). Now I want to find the terms that will be present in the expression after application of Chain rule for the term d^4(A)/dt^4. The exact definition of A is not know. It is just known that it is function of x & y. I just need the expression for d^4(A)/dt^4 in terms of dA/dt*dt/dx and so on. Could anyone please suggest a way of doing this in Maple?

Hi there. 

I'm making some 2D contour plots and am desperate to know what the values are which are assigned to the different contour levels. e.g., a red band must be reading value 120 (say) and an orange one 80, but how can I get this and show it on a legend in the plot? It's crucial to the value of the plot. 

Many thanks for any help!

David

Hello,

I'm trying to solve the following system in Maple but it doesn't show me any solution:

where x(0)=0 and y2(0)=0 , k>0,...

How can I show that the Least Square solution x = (A'.A)^-1.A'.y
Is different when A is an orthogonal matrix compared to an
overdetermined or underdetermind matrix.

Preferably transform the matrix using Singular Value Decomposition (SVD)
or something similar.

Thanx

How to play the Maple worksheet Alkylation Process Model Using DirectSearch

(http://www.maplesoft.com/applications/view.aspx?SID=1675)

There is some equivalence between GlobalOptimization commands: GetLastSolution and GlovalSolve and DirectSearch commands?

Gracias

Dear all

I made an array as

> T := Array(1..x, 1..6);

 where x = 1,000,000:

and then I wrote a loop for and after that I wanted to write the results as

> writedata("D:\\data\\test.txt", convert(T,array), float);

but I got an error as

> Error(in convert/list) object too large

What should I do now? It took more than 24 hours to run my program and I need the results as a text file. Please help me.