Proving multivariable limit exists where $\frac{a}{c} + \frac{b}{d} \gt 1$
Multivariable limit proof: $\lim\limits_{(x,y)\rightarrow (0,0)}\frac{\left|x\right|^a\left|y\right|^b}{\left|x\right|^c + \left|y\right|^d} = 0$