Question

[Hakai Nguyen]

Giai ho tim nghiem cua con nay

x^2-x-2x+2

Answer 1

[Đinh Đức Hùng]

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

\(\Leftrightarrow\left(x^2-2x+1\right)-\left(x-1\right)=0\)

\(\Leftrightarrow\left(x-1\right)^2-\left(x-1\right)=0\)

\(\Leftrightarrow\left(x-1\right)\left[\left(x-1\right)-1\right]=0\)

\(\Leftrightarrow\left(x-1\right)\left(x-2\right)=0\)

\(\Rightarrow\orbr{\begin{cases}x-1=0\\x-2=0\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}x=1\\x=2\end{cases}}\)