f:=x->x^3:
y[1]:=0.5:
y[3]:=subs(x=0.5,f(x)):
i := 2:
y[i] := y[i-1]-(y[1]-y[2+1])*(1/2):
i:=1:
g[i] := (y[i+1]-y[i+2])*x/(y[i]-y[i+1])+(y[i+2]*y[i]-y[i+1]*y[i+1])/(y[i]-y[i+1]):
g[i] := unapply(g[i], x):
h[i] := unapply(solve(y = g[i](x), x), y):
for i from 2 by 1 to 5 do
g[i]:=(f@h[i-1])(x);
g[i]:=unapply(g[i],x):
s:=solve(y=g[i](x),x):
h[i]:=unapply(s[1],y);
end do;

 for this code i got error "Error, (in kernels)...

I have a system of equations  AX=B where the matrix A from dimension 307x200, X from 200x1, and B from 307x1
How can I use Gauss elimination to solve these system of equations.

Can one find an integral representation of the solution of the following system of PDEs?

pde1 := diff(f(x,y),x) + A(x) * ( p11* f(x,y) + p12 + p13*x ) 
= p14 * B(y)/B(x) * diff(f(x,y),x);

pde2 := diff(f(x,y),y) + A(y) * ( p21* f(x,y) + p22 + p23*y ) 
= p24 * B(x)/B(y) * diff(f(x,y),y);

f(x,y) is the unknown function,
A(x) and B(x) are known functions,
p11, p12, etc. are real parameters.

If p14=0 and p24=0, the right-hand...

Dear All

I wonder if anyone can help me with something simple with odeplot.

Under some conditions that I can't pin down, Maple won't run the system for the whole time range I ask for, and it's not related to "maxfun". For example, in the simple lines of code below, Maple will only run out to t=3, no matter how I set the maxfun or stepsize. It is a general issue I have, for other systems as well.

Anyone know something? Thanks a lot, David.

(3 lines of code follow)

Hi guys please help me with the following.

When I evaluate the integral below

int(1/8*2^(1/2)*exp(-1/2*x^2/sigma^2)/(Pi^(5/2)*sigma)+1/8*2^(1/2)*exp(-1/2*x^2/sigma^2)*Q*exp(I*k*x)*exp(I*k*theta)/(Pi^(3/2)*sigma)+1/8*2^(1/2)*exp(-1/2*x^2/sigma^2)*Q/(Pi^(3/2)*sigma*exp(I*k*x)*exp(I*k*theta)), x = (-infinity .. infinity));    --------(1)

I get an expression with things like 

csgn(conjugate(sigma)) and 

Hi there....

I have a set P={4,5,6,7,12,14,15}

in order to create permutations of the numbers in set P into sets of 3 I did the following:

with(Statistics):

>P={4,5,6,7,12,14,15};

> O := combinat[permute](P, 3); 

But this does not produce permutation of the same number in a set as the integers in P can be repeated more than once....for example {4,4,4} or {15,15,15}?

How can I do so?

Any help will be appreciated

How can I solve the following problem using Maple:

Determine the special solution u(x,y) of the PDE

(  diff(u(x,y),x) )^2+( diff(u(x,y),y) )^2 = u(x,y)

such that the solution passes through the circle

x(s)=cos(s), y(s)=sin(s), z(s)=1        (0 ≤ s ≤ 2π) .

The solution obtained "by hand", i.e. without Maple, reads

u(x,y) = (1/4) ( 1+

Hi,

QQ.mw

I want to find the inverse function of the given function h(m),and also plot the inverse.I can't find any help to evaluate the inverse function in an explicit form.I plot the inverse though,but why its so ugly?How I can customize its domain & range?

I'm trying to use dsolve to get a numeric solution to a series of differential equations I have. I've got:

G := 1;

M := 1;

pT := 2;

OrbitEnergy :=  (r0) -> -1/r0+(1/2)*L^2/r0^2-L^2/r0^3;

OrbitDEs := diff(r(tau), [tau$2]) = -G*M/r(tau)^2+L^2/r(tau)^3-3*G*M*L^2/r(tau)^4, diff(phi(tau), tau) = L/r(tau)^2, diff(t(tau), tau) = sqrt(r(tau)/(r(tau)-2*G*M)+(diff(r(tau), tau))^2*r(tau)^2/(r(tau)-2*G*M)^2+r(tau)^3*(diff(phi(tau), tau))^2/(r(tau)-2*G*M));

Dear Sir / Madam,
Could you recommend me how to find the square root of the complex equation correctly?
My equation looks like this
sqrt(complex_equation_1^2 + complex_equation_2^2).

Hi,

I am trying to expand the following into a polynomial on maple:

to get  1 + x + 2 x^(2)+ 3 x^(3)+ 5 x^(4)+ 7 x^(5)+ 11 x^(6)+ 15 x^(7)+ 22 x^(8)+ 30 x^(9)+ 42 x^(10)...  

I tried to use the expand() code...

Consider the expression below.

r:=1/2 * exp(I*k*theta - 1/2*k^2*sigma^2)* sigma*sqrt(2*Pi) + 1/2 * exp(-I*k*theta - 1/2*k^2*sigma^2)* sigma*sqrt(2*Pi);       -------(1)

BY HAND I can factor out the sigma square root of 2 pi and one of the exponents to give.

sigma * sqrt(2*Pi...

Hi everybody:

I am having problems with the expression shown below.

X[1](s) = (s^2+2)*s/(1+s^4+3*s^2);

Specifically, when I try to find the inverse of the Laplace transform I get

x[1](t) = (1/10)*(sum((_alpha^2+4)*exp(_alpha*t), _alpha = RootOf(1+_Z^4+3*_Z^2)));

which obviously is not what I am looking for. Realizing that the problem must be the denominator I try to factor it using the factor command. That does not work either. If I do the factoring myself, that is

Can be developed in Maple, the figures mentioned in the following article: The Fundamental Theorem of Linear Algebra?

Im quite new to Maple, how do I extract the imaginary part of sqrt(I)? Im sure it is just Im(sqrt(I)) and Re(sqrt(I)), but the Im part just returns the real part againg for some reason, does anyone know what I am doing wrong here?

I'm using maple 9 by the way

>sqrt(I);