# Math Help - Integral

1. ## Integral

Prove that $\int_0^{\pi/4} d \phi e^{i \phi} e^{-R^2 \exp{(i 2 \phi)}} = 0$

2. ## Re: Integral

Hey strammer.

Hint: Try using the substitution u = e^(i*theta).

3. ## Re: Integral

Originally Posted by strammer
Prove that $\int_0^{\pi/4} d \phi e^{i \phi} e^{-R^2 \exp{(i 2 \phi)}} = 0$
It is not possible to prove it because it is not true :
Another integral

4. ## Re: Integral

Pardon me. It is only true as R tends to infinity.

Obvious !