Question

(X-1).(x^2-4)=0

Answer 1

=>(x-1)(x-2)(x+2)=0

=>\(x\in\left\{1;-2;2\right\}\)

Answer 2

`(x-1)(x^2 -4)=0`

`=>x=1` hoặc `x^2 = 4`

`=>x=1` hoặc `x^2 = 2^2 = (-2)^2`

`=>x=1` hoặc `x=2` hoặc `x=-2`

Vậy `x` \(\in\) `{1;2;-2}`

Answer 3

\(\left(x-1\right)\left(x^2-4\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x-1=0\\x^2-4=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=0+1\\x^2=0+4\end{matrix}\right.\)

`=>`\(\left[{}\begin{matrix}x=1\\x^2=4\end{matrix}\right.\)

`=>` \(x^2=\left(\pm2\right)^2\)

`=> x= (1,`\(\pm2\) `)`