Question

2/3 x ( x²-16 ) =0 tìm x

 

Answer 1

=>x^2-16=0

=>(x-4)(x+4)=0

=>x=4 hoặc x=-4

Answer 2

\(\dfrac{2}{3}x\left(x^2-16\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}\dfrac{2}{3}x=0\\x^2-16=0\end{matrix}\right.\)    \(\Rightarrow\left[{}\begin{matrix}x=0\\x^2=16=\left(\pm4\right)^2\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x=\pm4\end{matrix}\right.\)       Vậy \(x\in\left\{0;\pm4\right\}\)