   SEARCH HOME Math Central Quandaries & Queries  Question from alex, a teacher: I know that (-2)^2 is 4 but what is -2^2? Hi Alex,

When I look at -22 I see two operations, a negation and a power (square). The convention in mathematical expressions is that powers are performed before negations (also before additions, multiplications and divisions) so to evaluate -22 you first square the 2 to get 4 and then apply the negation to arrive at -4.

With (-2)2 the parentheses tell you to consider -2 as a single quantity and square it so (-2)2 = (-2) × (-2) = 4.

I hope this helps,
Penny

It's -4.

Please note that this is not really a question (or answer) about arithmetic; it is about the convention that the second expression shall be interpreted as -(2^2). There is no deep mathematical reason for this; it has just been found to be more convenient. That said, now that the convention is established, we all need to follow it; it's like driving on the right (or left) side of the road.

Good hunting!
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