show that $\displaystyle \lim _ { z \to 0 } f(z)$ does not exist where :
$\displaystyle (1) f(z)= \frac {Re z}{z} : Z \neq 0 \downarrow (2) 0 :z=0$ by definition {i know how i solve it by CR equations }
2. $\displaystyle \frac{{\text{Re} (z)}}{z} = \frac{{x^2 - xyi}}{{x^2 + y^2 }}$