Question

Giả phương trinh : √x^2+2x+1 -2 =0

Answer 1

\(\sqrt{x^2+2x+1}-2=0\\ \Leftrightarrow\sqrt{\left(x+1\right)^2}=2\\ \Leftrightarrow\left|x+1\right|=2\\ \Leftrightarrow\left[{}\begin{matrix}x+1=2\\x+1=-2\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=1\\x=-3\end{matrix}\right.\)

Answer 2

\(\sqrt{\left(x+1\right)^2}-2=0\)

⇒ \(\left|x+1\right|=2\)

⇒ \(\left[{}\begin{matrix}x=1\\x=-3\end{matrix}\right.\)

Answer 3

\(\sqrt{x^2+2x+1}-2=0\\ \Leftrightarrow\sqrt{\left(x+1\right)^2}=2\\ \Leftrightarrow\left|x+1\right|=2\\ \Leftrightarrow\left[{}\begin{matrix}x+1=2\\x+1=-2\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=1\\x=-3\end{matrix}\right.\)