Question

integral of trig function

Answer 1

please try to use this identity:
\[\Large 2\left( {1 - \cos \theta } \right) = 4{\left( {\sin \left( {\theta /2} \right)} \right)^2}\]

Answer 2

Nice use of the cos2θ identity

Answer 3

Another approach:
\[\sqrt{2(1-\cos\theta)}=\frac{\sqrt2\sin\theta}{\sqrt{1+\cos\theta}}\]then simply substitute \(x=1+\cos\theta\).

Answer 4

no word from @swift?