Use mathematical induction to prove that the statement is true for every positive integer n. 2 is a factor of n2 - n + 2
Do you know the steps for mathematical induction?
Not an induction proof, though nothing is stopping you from doing so... Here's one way you can reason that \(n^2-n+2\) must be even. Any even number plus 2 will be even, so you can ignore that part. Factoring, you have \[n^2-n=n(n-1)\] which is the product of an integer and the integer preceding it. If \(n\) is odd, then \(n-1\) is even. The product of an odd and an even gives you an even. Add 2 and it's still even. The same applies in the case that \(n\) is even and \(n-1\) is odd.
The question says use mathematical induction which requires 3 steps, I'm pretty sure here teacher will mark her off for not doing it in that way and giving that explanation you gave above, not going aginst you but I think that's her instructions
I understand, I was just giving a general argument. You can reconstruct the argument I provided so that it can involve a proof by induction (the claim that \(n(n-1)\) is always even, for example).
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