Question

The minimum value of $4x^2+4(2+x),x\in R$ is

Answer 1

$f\left(x\right)=4x^2+4x+8$

$f\left(x\right)=8x+4=0$

$fx=\frac{-4}{8}=\frac{-1}{2}$

$f\left(x\right)=1-2+8=7$