Hello, I bring here a problem with maple where I make a definite integral and appear suddenly in the solution a "csgn".

Here is the integral :

(1)

V(z) = (int(int(theta*R*(H-p)/(H*(L*L)*sqrt((R*(H-p)/H)^2+(z-p)^2)), p = 0 .. z), o = 0 .. 2*Pi))/(4*Pi*epsilon)

But i want the solution for z where 0

(2)

V := proc (z) options operator, arrow; (1/4)*(int(int(theta*R*(H-p)/(H*L*L*sqrt(R^2*(H-p)^2/H^2+(z-p)^2)), p = 0 .. z), o = 0 .. 2*Pi))/(Pi*epsilon) end proc

Hello, i'm having a problem whit my code for Finites Differences, but I don't really understand why. 

The principal error said this "

Error, (in fsolve) eq[2] is in the equation, and is not solved for"

The other errors come from this one, but the strange thing is my code work whit differents "h"

For example whit h=1 it works, but with h=2.5;0.5;0.1 It doesn't works.

Please help I'm kind of amateur whit Maple