Question

\(\sqrt{x^2-4x+4}=1\)

Answer 1

\(\sqrt{x^2-4x+4}=1\)

\(\Leftrightarrow\sqrt{\left(x-2\right)^2}=1\)

\(\Leftrightarrow\left|x-2\right|=1\)

\(\Leftrightarrow\left\{{}\begin{matrix}x-2=1\\x-2=-1\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x=3\\x=1\end{matrix}\right.\)

Answer 2

=>|x-2|=1

=>x-2=1 hoặc x-2=-1

=>x=1 hoặc x=3