Two answers: Choice B, Choice D
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Explanation:
Both of these represent the same idea. Square root notation is probably what you're more familiar with. It turns out that raising any positive number to the 1/2 power is the same as a square root. We can write
[tex]\sqrt{x} = x^{1/2}[/tex]
The 1/2 power notation may seem more clunky or confusing, but its helpful to extend to things like cube roots, fourth roots, etc.
The more general rule is
[tex]\sqrt[n]{x} = x^{1/n}[/tex]
which says the nth root of x is the same as x^(1/n).