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The similarity between the two below expressions always causes me doubt. To confirm, is there a fundamental difference between ...
1) sq. root ( [(x^2)] ) - two possible solutions (positive and negative, driven by the even exponent)
2) [(sq. root x)]^2 - one possible solution; even root yields one (positive) solution
hi! mystseen, this is my explanation...
sq. root(A) is a kind of equation. That means to find the value of sq. root(A) we should find the roots of equation A=x^2. As you can see we have two roots of A=x^2 as long as A is a positive number.(9=x^2 has two roots +-3).
sq. root ( [(x^2)] ), therefore, two values since x^2 is positive.
On the other hand, even if (sq. root x) has possibly two positive and negative values, [(sq. root x)]^2 has only one value since [(sq. root x)]^2 has only positive value. So [(sq. root x)]^2 has only one solution.
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