Answer
$\dfrac{x^4}{y^2}$
Work Step by Step
RECALL:
(1) $(a^m)^n=a^{mn}$
(2) $(ab)^m=a^mb^m$
(3) $a^{-m} = \dfrac{1}{a^m}, a \ne 0$
(4) $a^1 = a$
Use rule (2) above to obtain:
$=(x^2)^2(y^{-1})^2$
Use rule (1) above to obtain:
$=x^{2\cdot2}y^{(-1)\cdot2}
\\=x^4y^{-2}$
Use rule (3) above to obtain:
$=x^4 \cdot \dfrac{1}{y^2}
\\=\dfrac{x^4}{y^2}$
