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If y = x Sin x, find \(\frac{dy}{dx}\) when x = \(\frac{\pi}{2}\)

If y = x Sin x, find \(\frac{dy}{dx}\) when x = \(\frac{\pi}{2}\)
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  • A \(\frac{- \pi}{2}\)
  • B -1
  • C 1
  • D \(\frac{ \pi}{2}\)
Correct Answer: Option C
Explanation:
y = xsinx

\(\frac{dy}{dx}\) = \(1 \sin x + x \cos x\)

= \(\sin x + x \cos x\)

At x = \(\frac{\pi}{2}\)

= sin\(\frac{\pi}{r}\) + \(\frac{\pi}{2} \cos {\frac{\pi}{2}}\)

= 1 + \(\frac{\pi}{2}\) × 10

= 1

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