i 3 wjechało prosze o pomoc!

[tex]x\neq 0\ \ i\ \ x+3\neq 0\\\\x\neq 0\ \ i\ \ x\neq -3\\\\D=R\setminus \left\{ 0,-3\right\}[/tex]
[tex]\frac{4x+12}{x^2} * \frac{x^2+4x}{x+3 } = \frac{4 (x+3)}{x^2} * \frac{x( x +4 )}{x+3 } =\frac{4(x+4)}{x}[/tex]