Question

|x*(x-3)|=10x

Answer 1

Ta có: \(\left|x\left(x-3\right)\right|=10x\)

\(\Leftrightarrow\left[{}\begin{matrix}x\left(x-3\right)=10x\\x\left(x-3\right)=-10x\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x\left(x-3-10\right)=0\\x\left(x-3+10\right)=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x-13=0\\x+7=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=13\\x=-7\left(loại\right)\end{matrix}\right.\)

Vậy: S={0;13}