CBSE Class 12 Mathematics 2026: question 27(b)
Set in the CBSE Class 12 board exam of 2026, paper 65/5/1, section C, question 27(b), for 3 marks. Try it first; the hints and our step-by-step solution are below.
Q27(b) · 3 marks · Short answerIntegrals
Evaluate :
Source: official question paper from cbse.gov.in (PDF). See it in the full 2026 board paper, set 65/5/1.
Hints
Open one hint at a time and try again before the next.
Hint 1
Complete the square inside the square root.
Hint 2
The integral now has the standard form .
Hint 3
Substitute and into the antiderivative.
Step-by-step solution
Each step shows the marks it earns, as an examiner would award them. Checked by an independent re-solve from the question paper.
- 1 mark
Complete the square: , so
- 1 mark
Using :
- 1 mark
Answer:
Where the marks are
- Completes the square as (1 mark)
- Correct antiderivative (1 mark)
- Correct evaluation at the limits (1 mark)
Revise the chapter
- Chapter: Integrals (notes, formulas, where marks are lost and every past question)
More questions from Integrals
The question is transcribed from the official paper; figures are described in words. The solution, hints and chapter tag are ours. Spotted an error? Write tosupport@questionbuddy.in.