Let $f(x):\mathbb{R}^2\rightarrow\mathbb{R}$ via $$f(x)=\begin{cases}
\dfrac{x\_1^2}{x\_1+x\_2}, &\text{ if }x\_1+x\_2\neq 0\\
0, & \text{ otherwise } 
\end{cases}$$
Does $\lim\_\limits{x\rightarrow 0}f(x)$ exist?
I tried several sequences and it seems that the limit $=0$, but I haven't found a good way to prove it using $\varepsilon-\delta$.