GCSE · Algebraic proof

Expressing generality — the language of proofExam-style questions

Why testing examples proves nothing, how 2n, 2n + 1 and n, n + 1, n + 2 encode "any even", "any odd" and "consecutive", and when one counterexample settles everything.

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

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  1. 1
    nn is an integer.

    (a) Write down an expression, in terms of nn, for any odd number.

    (b) Write down expressions for the next two odd numbers after 2n+12n + 1.
    Level 2 · 2 marksTry it