Question

Evaluate: $\int si{n}^2\theta d\theta$

Answer 1

$\int {\sin }^2\theta d\theta$

$=\frac{1}{2}\int 2{\sin }^2\theta d\theta$

$=\frac{1}{2}\int (1-\cos 2\theta )d\theta$

$=\frac{1}{2}[\theta -\frac{\sin 2\theta }{2}]$

$=\frac{\theta }{2}-\frac{\sin 2\theta }{4}+c$