Question

Tìm x biết 

a) \(\left|x+1\right|\) +2x=-2

b) x^2-6x+9=1

Answer 1

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

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

b: \(\Leftrightarrow\left(x-3\right)^2=1\)

\(\Leftrightarrow\left[{}\begin{matrix}x-3=1\\x-3=-1\end{matrix}\right.\Leftrightarrow x\in\left\{4;2\right\}\)