Hello everybody.
In the attached code, when I compute q1 by NIntegrate is equal to 0.000195151 while the true value for q1 is 0.0001943732. Of course \Sigma(T) is computed correctly.
What is the reason for this slight difference?
In fact, I tried to write the below formula 
like this: 
Is it true? What's the problem?
At last, I should say that I must use NIntegrate in my computation.
Attachments:
