Answer :
[tex]y=x^2-4x+4\\\\a=1;\ b=-4;\ c=4\\\\a > 0\ then\ minimum:\\\\\frac{-b}{2a}=\frac{-(-4)}{2\cdot1}=\frac{4}{2}=2\\\\y_{min}=2^2-4\cdot2+4=4-8+4=0\\\\\\domain:x\in\mathbb{R}\\\\\\range:y\in\left<0;\ \infty\right)[/tex]
