Question

can someone explain me this example.... please

Answer 1

oops i meant
b) a denominator of 2

Answer 2

you have an exponent of \(-\frac{1}{2}\) which has three components,
a) an numerator of 1
b) a denominator of 2
c) a minus sign

they mean in turn
a) take the first power \(9^1=9\)
b) that the square root \(\sqrt{9}=3\)
c) take the reciprocal the reciprocal of 3 is \(\frac{1}{3}\)