Question

\(7-\left(2x-\dfrac{1}{3}\right)^2=3\)

Answer 1

`7-(2x-1/3)^2=3`

`=>(2x-1/3)^2=7-3`

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

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

`=>2x-1/3=2` hoặc `2x-1/3=-2`

`=>2x=2+1/3` hoặc `2x=-2+1/3`

`=>2x=6/3+1/3` hoặc `2x=-6/3+1/3`

`=>2x=7/3` hoặc `2x=-5/3`

`=>x=7/3:2` hoặc `x=-5/3:2`

`=>x=7/3 . 1/2` hoặc `x=-5/3 . 1/2`

`=>x=7/6` hoặc `x=-5/6`

Vậy `x in{7/6;-5/6}`

Answer 2

\(7-\left(2x-\dfrac{1}{3}\right)^2=3\)
\(\Rightarrow\left(2x-\dfrac{1}{3}\right)^2=4\)
\(\Rightarrow\left[{}\begin{matrix}2x-\dfrac{1}{3}=2\\2x-\dfrac{1}{3}=-2\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}2x=\dfrac{7}{3}\\2x=-\dfrac{5}{3}\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{7}{6}\\x=-\dfrac{5}{6}\end{matrix}\right.\)