David,

We can get linguistic here and simply ask how does one write -2 squared in a math equation? I was always taught the squared means raised to the power of 2 which would be -2^2 for -2 squared and since we know that -2 squared is 4 there's the answer.

To deal with the sitckier folks who might say that -2 squared is written as -1*2^2 then we ask how does one write 2 squared? I can't imagine anyone suggersting that 2 squared is written as 1*2^2, that would indicate that 2 is written as 1*2 or that -2 is written as -1*2 (which when reduced equals -2) ahem, are we sufficiently going in circles here yet?

>I was going to introduce an odd power example yesterday but it doesn't prove anything one way or the other because they'd just say the negative result was because of a negation operation applied to the exponentiation result... I was also thinking about a negative power ie 2 ^ -2 but concluded that wouldn't illustrate it either.
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