Ta có :
\(f\left(x\right)=x^2-6x+9\)
\(\Leftrightarrow f\left(3\right)=3^2-6.3+9\)
\(\Leftrightarrow f\left(3\right)=0\)
\(\Leftrightarrow f\left(0\right)=0^2-6.0+9\)
\(\Leftrightarrow f\left(0\right)=9\)
Vậy..
ta có :f(x)=x^2-6x+9
=>f(3)=3^2-6.3+9
=>f(3)=9-18+9
=>f(3)=-9+9
=>f(3)=0
cậu làm như thế với f(0) nhé
\(y=f\left(x\right)=x^2-6x+9\)
➩\(f\left(3\right)=3^2-6\cdot3+9=9-18+9=0\)
Vậy : \(f\left(3\right)=0\)
➩\(f\left(0\right)=0^2-6\cdot0+9=0-0+9=9\)
Vậy : \(f\left(0\right)=9\)