The question asks to find the limit (x,y) -> (0,0) and this is the function:

$\displaystyle \frac{x^2 sin(y)^2}{x^2 + 5y^2}$

so i tried approaching (0,0) from y=cx and i get this:

$\displaystyle \frac{x^2 sin(cx)^2}{x^2(1 + 5c)}$

but im not quite sure where to go from here??

an explanation would be greatly appreciated