Suppose we have a statement (say an equation) P(n, m), and we want to prove it works for arbitrary n and m.(adsbygoogle = window.adsbygoogle || []).push({});

Either

(1) It is sufficient to define Q(n) = P(n,m) or R(m) = P(n,m) and prove either Q(n) or R(m) by induction

(2) It is necessary to prove that P(n,m) => P(n+1,m) and P(n, m) => P(n, m+1), in addition to the base cases, to show that it works for arbitrary n and m.

Which one is correct !?

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# Induction with more than one variable

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