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Student Support Forum: 'Problem with integrals.' topicStudent Support Forum > General > "Problem with integrals."

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JOSSE Thomas
10/15/10 09:29am

Hi,
I have a problem with the Integrate function.
My code is the following:
R = 1;
H = 4;
L1 = 17;
t[z_] := If[z > 0, 0, If[z + R < 0, 0, ArcCos[-z/R]]];
y[u_, r_] := r Sin[u];
z[u_, r_] := -r Cos[u];
zd[x_, T_] :=
If[T == Pi/2, 0,
If[T == 0, R - H,
If[x < X1[T] || x > X2[T], 0, Tan[T] (x - H/Sin[T])]]];

A[x_] := 2*Integrate[-z[t, R] Derivative[1, 0][y][t, R], {t, 0, x}] +
2*y[x, R]*z[x, R];

Cas[T_] :=
If[T == 0, If[H < 0, 0, If[H > R, 5, 4]],
If[H > (L1 + R/Tan[T]) Sin[T], 5,
If[L1*Sin[T] < H && H < R/Cos[T], 4,
If[H < 0, 0,
If[H < Min[R*Cos[T], L1*Sin[T]], 1, If[H < L1*Sin[T], 2, 3]]]]]];

X1[T_] :=
If[Cas[T] == 2 || Cas[T] == 3, (H - R/Cos[T])/Sin[T] + R*Tan[T],
If[Cas[T] == 5, L1, 0]];
X2[T_] :=
If[Cas[T] == 0, 0,
If[Cas[T] == 3 || Cas[T] == 4 || Cas[T] == 5, L1, H/Sin[T]]];

Compil[j_, T_] := A[t[zd[j, T]]];
V1bis[T_] := Integrate[Compil[j, T], {j, X1[T], X2[T]}];
V1bis[0.35]


I know that it's a little bit complicated but I don't understand why I can't have a real value of V1bis.
Can anyone see my error and tell me how to do it right?

Thank you

PS: Sorry for my bad english.

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Subject (listing for 'Problem with integrals.')
Author Date Posted
Problem with integrals. JOSSE Thomas 10/15/10 09:29am
Re: Problem with integrals. Forum Modera... 10/20/10 4:43pm
Re: Problem with integrals. Thomas JOSSE 11/03/10 07:50am
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