I need an explanation on how to work out

Question

negative exponents. Example: (3a^-2b^3)^-2

Answer 1

(3a^-2b^3)^-2 =
1/(3a^-2*b^3)2 =
Square everything inside the parenthesis:
1/(9a^-4*b^6) = a^4/9b^6.

NOTE: Never leave neg. exponents in your answer. To remove the neg. exponent
from 1/a^-4, multiply numerator and
denominator by a^4:
1/a^-4 = 1*a^4/a^-4*a^4 = a^4/1 = a^4.
We,actually, moved a^-2 to the numerator
and changed the sign.

Answer 2

Correction: We,actually, moved a^-4 to
the numerator and changed the sign of the exponent.