n is an integer greater than 1. Prove algebraically that n^2 – 2 – (n – 2)^2 is always an even number.

1) Expand the brackets: (n-2)2 = (n-2)(n-2) = n2 - 2n - 2n +4 = n2 - 4n + 42) Substitute this into the original expression: n2- 2 - (n2 - 4n +4) = n2 - 2 - n2 + 4n - 4 = 4n - 6 3) Reduce this: 4n - 6 = 2(2n - 3)4) Conclusion: This is always an even number as for all values of n the expression is a multiple of 2

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