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10Product rule derivative

Let f(x)=x2sin⁡x\displaystyle f(x) = x^2 \sin x. Find f′(π)\displaystyle f'(\pi). Give the answer to 3 decimal places.

Use the product rule: f'(x) = 2x·sin x + x²·cos x. At x = π, sin π = 0 and cos π = −1, so f'(π) = −π² ≈ −9.870.

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