Evaluate each of the following integral: `int_0^(pi//4)sin2x\ dx`

Explanation

Suppose that `I=\int_{0}^{\pi / 4} \sin 2 {xdx}`


`=[-\frac{\cos 2 x}{2}]_{0}^{\pi / 4}`




`=\frac{1}{2}[-\cos 2 {x}]_{0}^{\pi / 4}`


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