GCSE · Algebraic proof

Proving divisibility resultsExam-style questions

The expand–collect–factorise engine: to prove "always a multiple of k", exhibit the expression as k × (whole number) — and say so.

13 questions · GCSE (Higher) level · mark scheme and worked solution on each · no sign-up to try

DifficultyAllLevel 3Level 4Level 5
  1. 1
    Prove that the difference between the squares of any two consecutive even numbers is a multiple of 4.
    Level 5 · 3 marksTry it
  2. 2
    Prove that n3−nn^3 - n is a multiple of 6 for every integer nn.
    Level 5 · 4 marksTry it
  3. 3
    Prove that the sum of any four consecutive integers is never a multiple of 4.
    Level 5 · 3 marksTry it
  4. 4
    Prove that n2+3nn^2 + 3n is even for every integer nn.
    Level 5 · 3 marksTry it
  5. 5
    Prove that n3+3n2+2nn^3 + 3n^2 + 2n is a multiple of 6 for every integer nn.
    Level 5 · 4 marksTry it