# Integral

• Jan 31st 2013, 12:36 PM
strammer
Integral
Prove that $\int_0^{\pi/4} d \phi e^{i \phi} e^{-R^2 \exp{(i 2 \phi)}} = 0$
• Jan 31st 2013, 04:10 PM
chiro
Re: Integral
Hey strammer.

Hint: Try using the substitution u = e^(i*theta).
• Feb 1st 2013, 03:09 AM
JJacquelin
Re: Integral
Quote:

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
• Feb 1st 2013, 06:31 AM
strammer
Re: Integral
Pardon me. It is only true as R tends to infinity.
• Feb 1st 2013, 06:56 AM
JJacquelin
Re: Integral
Obvious !