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CBSE Class 12 Mathematics 2026 Supplementary Paper 65/7/2 · Q283 Marksabsolute_extrema

CBSE Class 12 Mathematics 2026 Supplementary Paper 65/7/2 · Question 28 (Applications Of Derivatives)

Find the sum of maximum and minimum values of sin x(1+cos x) on [0,π].

✅ Step-by-Step Solution

Final Answer: 3√3/4.
  1. The derivative is cos x+cos 2x=(2cos x−1)(cos x+1).
  2. The interior critical point is π/3. The endpoints both give zero, and the function is nonnegative.
  3. The value at π/3 is 3√3/4, so adding the minimum zero gives 3√3/4.

📋 CBSE Stepwise Marking Scheme

  • [0.5 marks] The derivative is cos x+cos 2x=(2cos x−1)(cos x+1).
  • [2 marks] The interior critical point is π/3. The endpoints both give zero, and the function is nonnegative.
  • [0.5 marks] The value at π/3 is 3√3/4, so adding the minimum zero gives 3√3/4.

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All Questions in CBSE Class 12 Mathematics 2026 Supplementary Paper 65/7/2

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