Why must 2 numbers be even?

[Guest]

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[Guest]

I'm confused by your formula because you only wrote (n-1)n(n+1). I'm not sure if you mean 3 or 4 consecutive integers, and didn't not whether or not they need to be positive.

If you meant 3, then there is a possibility that the integers could have two evens (2,3,4) or two odds (1,2,3).

If you have four consecutive integers there will always be two evens and two odds no matter which way you cut it. The factors of 4 are (2*2). One of the characteristics of an even number is that its divisible by two. So when you multiply and two numbers that contain 2's, the result will be divisible by 4.

The tricky part comes when you have -2, -1, -0, 1. Since the result is 0, I believe 0 is divisible by 4.

Hope this helps

[RonPurewal]

which book? what is the source of this problem?

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