Answer:
[tex]\frac{16y^6}{x^2}[/tex]
Step-by-step explanation:
[tex](\frac{4xy^3}{x^2})^2 = \frac{16x^2y^6}{x^2}[/tex]
[tex]\frac{x^2}{x^2}[/tex] cancels out leaving you with [tex]\frac{16y^6}{x^2}[/tex]
Hope this helps!