Question

x^2-3^2=0

tìm x trình bày ra luôn

 

Answer 1

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

Answer 2

\(\Leftrightarrow x\in\left\{3;-3\right\}\)

Answer 3

\(x^2-3^2=0\Leftrightarrow\left(x-9\right)\left(x+9\right)=0\)

\(TH1\left(x-9\right)=0\Leftrightarrow x=9\)

\(TH2\left(x+9\right)=0\Leftrightarrow x=-9\)