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Induction

2 videos
Proof by induction is a core tool. This tutorial walks you through the general idea that if 1) something is true for a base case (say when n=1) and 2) if it is true for n, then it is also true for n+1, then it must be true for all n! Amazing!

Proof by induction

VIDEO 9:23 minutes
Proving an expression for the sum of all positive integers up to and including n by induction

Alternate proof to induction for integer sum

VIDEO 3:32 minutes
Another way to prove the expression for the sum of all positive integers up to and including n