The integral is .

Consider .

Substitute .

and .

Apply derivative on each side with respect to .

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Substiute the corresponding values in the integral.

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Substitute and .

.

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(a) Apply integration limits.

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(b)

Apply trigonometric limits in equation .

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If then .

If then .

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(a) By the integration limits : .

(b) By the limits obtained by the trigonometric substitution: .