Raising a negative value to a fraction power?

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Ahmed 2020-11-24

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评论： Ahmed 2020-11-24

I am rasing a negative value to a fraction power. Depending on how I write the operation (putting the negative value in parenthesis or not), the answer changes (see below)? Am I missing something?

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Answer 1

Alan Stevens 2020-11-24

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Exponentiation has a higher priority than negation, so -2^1.2 is -(2^1.2), this results in a negative real. On the other had (-2)^1.2 raises a negative number to a fractional power, because parentheses take priority over exponentiation, and the result is a complex number.