Phương trình \(x^2-3x+2=0\) có nghiệm là:
\(x=1;x=-2\)\(x=-1;x=2\)\(x=-1;x=-2\)\(x=1;x=2\)Hướng dẫn giải:Ta có: \(x^2-3x+2=0\Leftrightarrow\left(x^2-x\right)-\left(2x-2\right)=0\Leftrightarrow x\left(x-1\right)-2\left(x-1\right)=0\)
\(\Leftrightarrow\left(x-1\right)\left(x-2\right)=0\Leftrightarrow\left[{}\begin{matrix}x-1=0\\x-2=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=1\\x=2\end{matrix}\right.\)