The function is .

Rewrite the expression:

Assume  and .

Consider .

Differentiate on each side with respect to .

Consider .

Differentiate on each side with respect to .

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Apply derivative on each side with respect to .

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Rewrite the expression using chain rule.

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Fundamental theorem of calculus: 

If  is continuous on , then the function  is defined by  is continuous on  and differentiable on , then .

Here  and .

From the fundamental theorem of calculus, part 1, .

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Replace  and  in above expression.

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The derivative of the function .

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The derivative of the function .