Y12 Proof by induction question

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I was fine with the solution up until the third-to-last line. What exact change was made for the fourth-to-last line to become the third-to-last line? It wasn’t clearly explained in the solution.

(edited 6 months ago)

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Reply 2

Muttley79

Original post by Sha.xo527

I was fine with the solution up until the third-to-last line. What exact change was made for the fourth-to-last line to become the third-to-last line? It wasn’t clearly explained in the solution.

Where's the question? Usually we assume it true for some n = k ... why do you hvae k + 1 in your assumption?

Reply 3

ghostwalker

Original post by Sha.xo527

I was fine with the solution up until the third-to-last line. What exact change was made for the fourth-to-last line to become the third-to-last line? It wasn’t
clearly explained in the solution.