prove-that-cos-2-log-cos-sin-cos-sin-1-2-sin-2-log-tan-pi-4-1-2-log-cos-2-

Question Number 147835 by peter frank last updated on 23/Jul/21

p r o v e t h a t

\int \cos 2 θ l o g (\frac{\cos θ + \sin θ}{\cos θ - \sin θ}) = \frac{1}{2} \sin 2 θ l o g [\tan (\frac{π}{4} + θ) + \frac{1}{2} \log (\cos 2 θ)