Proof by induction is a really useful way of proving results about the natural numbers. If you haven't met this powerful technique before, this module will introduce you to the idea and method of induction. If you're already familiar, check out some of the problems and STEP questions that can be answered in this way!
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An introduction to mathematical induction
This article gives an introduction to mathematical induction, a powerful method of mathematical proof.
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Some induction examples
Some statements which can be proved using induction, and some example proofs.
problem
Dirisibly yours
Age
16 to 18
Challenge level
Find and explain a short and neat proof that 5^(2n+1) + 11^(2n+1) +
17^(2n+1) is divisible by 33 for every non negative integer n.
problem
Tens
Age
16 to 18
Challenge level
When is $7^n + 3^n$ a multiple of 10? Can you prove the result by two different methods?