# Problem with integration

Hi. The problem is present with W10 SageMath notebook 9.1. The calcul take long time (+ one heure) and i don't get the results

```
var('z,w,x,om')
E1=200
nu=0.33
rho1=7850
Pi=pi.n()
ah=5
e0=0.25
h=1/ah
em=1-sqrt(1-e0)
aa=Pi*z/(2*h)+Pi/(4);
Ez=E1*(1-e0*(cos(aa)));
rhoz=rho1*(1-em*(cos(aa)));
Q11=Ez;
A11=integral(Q11,z,-h/2,h/2);
B11=integral(Q11*z,z,-h/2,h/2);
D11=integral(Q11*z^2,z,-h/2,h/2);
rhoz1=rhoz
rhoz2=rhoz*z
rhoz3=rhoz*z**2
I0=rhoz1.integral(z,-h/2,h/2);
I1=rhoz2.integral(z,-h/2,h/2);
I2=rhoz3.integral(z,-h/2,h/2);
e1=-I0*om^2/A11;
e2=I1*om^2/A11;
e3=B11/A11;
e4=-(B11*e1+I1*om^2)/(B11*e3-D11);
e5=-I0*om^2/(B11*e3-D11);
e6=(I2*om^2-B11*e2)/(B11*e3-D11);
```