The integral is .
The indicated trignometric subustitution is .
Subustiute and
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Trigonometric identity : .
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Consider .
Apply derivative on each side with respect to .
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Subustiute and
in the integral.
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Sum and difference rule of integration :.
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Substitute in the above integral.
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The indicated trignometric subustitution is .
In the right triangle and
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Find
Therefore, substitute in equation
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Associate Right Triangle :
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