WEBVTT

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Here is the problem: derivative of sin(x) cubed.

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Find the derivative of sin(x) cubed with respect to x.

3
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Power rule with the chain rule: d by d x[u to the power n] equals n times u to the power n minus 1 times u prime.

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d by d x[sin x] equals cos x.

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Combine and simplify.

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So the answer is f prime of x equals 3sin(x) squared times cos(x).

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The derivative is built from the outside in: sums split into terms, constants factor out, products and quotients use their rules, and every composite function multiplies by the derivative of its inside (chain rule).

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Cross-checked numerically against an independent symbolic differentiator at 8 sample points, which checks out.