Question

a) (x-1/4)^2 =4/9

Answer 1

`(x-1/4)^2=4/9`

`(x-1/4)^2=(2/3)^2=(-2/3)^2`

\(\left[{}\begin{matrix}x-\dfrac{1}{4}=\dfrac{2}{3}\\x-\dfrac{1}{4}=-\dfrac{2}{3}\end{matrix}\right.\\ \left[{}\begin{matrix}x=\dfrac{11}{12}\\x=-\dfrac{5}{12}\end{matrix}\right.\)

 

Answer 2

a) Ta có: \(\left(x-\dfrac{1}{4}\right)^2=\dfrac{4}{9}\)

\(\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{1}{4}=\dfrac{2}{3}\\x-\dfrac{1}{4}=-\dfrac{2}{3}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{11}{12}\\x=\dfrac{-5}{12}\end{matrix}\right.\)

Vậy: \(x\in\left\{\dfrac{11}{12};-\dfrac{5}{12}\right\}\)