Question

giải phương trình (x-2)²(x-9) = 0 

 

Answer 1

\(\left(x-2\right)^2\left(x-9\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}\left(x-2\right)^2=0\\x-9=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}\left(x-2\right)\left(x-2\right)=0\\x=9\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=2\\x=9\end{matrix}\right.\)

Answer 2

\(\left(x-2\right)^2\left(x-9\right)=0\)

\(\Leftrightarrow\left(x-2\right)\left(x-2\right)\left(x-9\right)=0\)

\(\Leftrightarrow x-2=0hoặcx-9=0\)

\(\Leftrightarrow x=2hoặcx=9\)

Vậy phương trình có nghiệm là:\(S=\left\{2;9\right\}\)