you did $\displaystyle \lim_{\rho \rightarrow 0}\frac{\rho^{2}\cos^{2}\theta\cdot\rho^{2} \sin \theta}{\rho^{2}}$?

why is it so? After all $\displaystyle x=\rho \cdot \cos\theta$ and $\displaystyle y=\rho \cdot \sin\theta$

After trying to understand various problems for 10hours, almost everyone would start to understand something

In other thread I found that $\displaystyle \lim_{(x,y)\rightarrow(0,0)}y^2\ln(x^2+y^2)$ => $\displaystyle y^2 \ln(x^2+y^2)=2r^2 \sin^2 \theta \ln r.$

In what way does 2 appear?