The integral is .

Rewrite the integral.

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Assume .

Differentiate on each side.

Substitute corresponding values in the integral.

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Trigonometric identity: .

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Replace  in above expression.

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Consider the antiderivative function by taking  as  .

Graph :

Graph the integrand function  and its antiderivative .

Observe the graph,

When  is negative, then  is decreasing and  is positive, then  is increasing.

Hence the curve  is derivative of the curve .

Therefore,  is antiderivative of the integrand function .

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Graph : 

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