Answer: No, it can never be negative.
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Step-by-step explanation:
Consider the expression x^2
If x were some negative number, say x = -3, then
x^2 = (-3)^2 = 9 which is a positive result.
Picking any negative number for x will make x^2 positive.
We can think of it like this
(-3)^2 = (-3)*(-3) = 9
The two negatives multiply to a positive.
This also happens with exponents 4,6,8, etc. Any even exponent will have an even number of negative signs, all of which cancel out.