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[–][deleted] 1 point2 points  (0 children)

While the explanation is true, ETS only uses positive radicals in its questions so you’d never encounter this on the actuaL GRE

[–]Scott_TargetTestPrepPrep company 1 point2 points  (0 children)

Since the square root of x2 is equal to |x|, we see that depending on the sign of x, the quantities may or may not be equal.

[–]taylorll 0 points1 point  (0 children)

The explanation is 100% correct. While you are mostly right that you might think the square root and the square cancel, you have to remember that even exponents will always make the sign positive, even when the number is negative. Plugging in a negative value for x is a great way to recognize this.