Skip to main content
A-LevelFurther MathematicsIntegration9231/12 · Oct/Nov 2017 · Q811 Marks

Let Iⁿ = ∫(from 0 to π/4) secⁿx dx for n > 0.

  1. (i)Find the value of I₂.[2]
  2. (ii)Show that, for n > 2, (n - 1)Iⁿ = 2ⁿ⁻¹ + (n - 2)Iⁿ⁻².[5]
  3. (iii)The curve C has equation y = sec³x for 0 ≤ x ≤ π/4. The region R is bounded by C, the x-axis, the y-axis and the line x = π/4. Find the volume of revolution generated when R is rotated through 2π radians about the x-axis.[4]

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2017). The mark or mark type is shown in brackets.

  1. [2] M1A1
  2. [1] M1 For setting up integration by parts (u = secⁿ⁻²x, dv/dx = sec²x)
  3. [2] M1A1 For applying integration by parts: [secⁿ⁻²x tanx] - ∫ (n-2)secⁿ⁻²x tan²x dx
  4. [1] M1 For using tan²x = sec²x - 1 and splitting the integral
  5. [1] A1 AG For rearranging and showing (n - 1)Iⁿ = 2ⁿ⁻¹ + (n - 2)Iⁿ⁻²
  6. [1] M1
  7. [1] M1
  8. [1] M1
  9. [1] A1

Write your answer and get it marked

On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.

Sign up free →

About this question

Topic
Integration, A-Level Further Mathematics (syllabus 9231). Structured question, 11 marks.
Source
A-Level Further Mathematics, Oct/Nov 2017 Paper 1 Variant 2, question 8.

Questions and mark schemes are from past examination papers and remain the copyright of the exam board. How Oracle Prep builds its content

Related Further Mathematics questions

© 2026 Oracle Prep