Evaluating $\int (\sin x)^2\,dx$

Question

Evaluate $$\int (\sin x)^2\,dx$$

Anyone can guide me for this?

Thank you!

Answer 1

Write $(\sin x)^{2} = \dfrac{1 - \cos 2x }{2}$. No need of substitution or by parts

Answer 2

Hint: $\quad \sin^2 x = \tfrac{1}{2}( 1 - \cos 2x)$