Question

(2x-1)\(^2\)=4 Tìm x

Answer 1

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

`=> (2x - 1)^2 = (+-2)^2`

`=> 2x - 1 = 2` hoặc `2x - 1 =-2`

`=> 2x = 2 +1 ` hoặc `2x = -2 +1`

`=> 2x = 3` hoặc `2x = -1`

`=> x = 3/2` hoặc `x =-1/2`

Vậy `x \in {3/2 ; -1/2}`

Answer 2

\(\left(2x-1\right)^2=4\\ \Rightarrow\left\{{}\begin{matrix}2x-1=2\\2x-1=-2\end{matrix}\right.\\ \Rightarrow\left\{{}\begin{matrix}x=\dfrac{2+1}{2}=\dfrac{3}{2}\\x=\dfrac{-2+1}{2}=-\dfrac{1}{2}\end{matrix}\right.\)

vậy x \(\in\left\{\dfrac{3}{2};-\dfrac{1}{2}\right\}\)