1. nenegative
2.
[tex]\it a)\ V\Big(-\dfrac{b}{2a},\ \ -\dfrac{\Delta}{4a}\Big)\\ \\ \\ -\dfrac{b}{2a}=-\dfrac{4}{2}=-2;\ \ \ -\dfrac{\Delta}{4a}=-\dfrac{16-12}{4}=-1;\ \ V(-2,\ \ -1)[/tex]
[tex]\it b) \ \ Gf\cap Oy=P(0,\ \ y) \Rightarrow y=f(0)=3;\ \ Gf\cap Oy=P(0,\ \ 3)[/tex]
[tex]\it c)\ \ f(x)=0 \Rightarrow x^2+4x+3=0 \Rightarrow x^2+3x+x+3=0 \Rightarrow \\ \\ \Rightarrow x(x+3)+(x+3)=0 \Rightarrow (x+3)(x+1)=0 \Rightarrow x_1=-3,\ \ x_2=-1\\ \\ Gf\cap Ox=\{A(-3,\ 0);\ \ B(-1,\ 0)\}[/tex]
