Multivariate limit

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I have troubles with such limit

$$ \lim_{(x,y)\rightarrow(0,0)} \frac{x^3}{y^4+2\sin^2{x}}$$

Nothing works, as I approach on any line or curve I get limit equal to $0$.
I try polar coordinates - also nothing, still $0$. I try to bound it somehow - I get infinity. However, wolfram tells that there is no limit for the function in $(0,0)$. If I can get any hint, that would be great.

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Call your function $f(x,y)$. Note that $|f(x,y)| \le |f(x,0)|$ and $$ \lim_{x \to 0} f(x,0) = \lim_{x \to 0} \dfrac{x^3}{2\sin^2(x)} = 0$$