A fractional index of a half is the equivalent of finding a square root.

Using the rules for multiplying powers, notice that:

9^½ x 9^½ = 9¹

Which is then the equivalent of:

√9 x √9 = 9

Therefore, 

9^½ = √9 = 3

Understanding this explanation is helpful, but the important thing is to remember that any number to the power of a half, simply means the square root of that number. 

Shall we try some questions now?

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