Mathematics

$$ \int_{0}^{\frac{\pi}{2}} \sin \theta \cdot \sin 2 \theta d \theta $$


ANSWER

$$ \frac{2}{3} $$


SOLUTION
$$\displaystyle\int _{0}^{\pi/2} \sin \theta.\sin 2\theta d\theta=2\int ^{\pi/2}_{0}\sin ^2 \theta. \cos \theta d\theta=\bigg[\frac{2\sin ^3 \theta}{3}\bigg]^{\pi/2}_{0}=\dfrac{2}{3}$$
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Single Correct Medium Published on 17th 09, 2020
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