What does 2 to the half power equal?

Answer 1

21/2 = √2 ≈ 1.414

The rules of indices are that when multiplying add them.

21/2 x 21/2 = 21/2 + 1/2 = 21 = 2

So multiplying 21/2 by itself gives 2.

But what number multiplied by itself gives 2?

The answer is the square root of 2.

Thus 21/2 is the square root of 2.