The integral is .
Consider .
Substitute .
and
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Apply derivative on each side with respect to .
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Substitute 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
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If then
.
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(a) By the integration limits: .
(b) By the limits obtained by the trigonometric substitution: .