Question

\(\left|3x^2-8x+5\right|=\left|x^2+x-2\right|\)

Answer 1

\(\Leftrightarrow\left[{}\begin{matrix}3x^2-8x+5=x^2+x-2\\3x^2-8x+5=-x^2-x+2\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}2x^2-9x+7=0\\4x^2-7x+7=0\end{matrix}\right.\)

\(\Leftrightarrow2x^2-9x+7=0\)

\(\Leftrightarrow2x^2-2x-7x+7=0\)

=>(x-1)(2x-7)=0

=>x=1 hoặc x=7/2