Question

(2x -1 )² = 3

Answer 1

\(\left(2x-1\right)^2=3\)

\(\Leftrightarrow4x^2-4x+1-3=0\)

\(\Leftrightarrow4x^2-4x-2=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1+\sqrt{3}}{2}\\x=\dfrac{1-\sqrt{3}}{2}\end{matrix}\right.\)

Vậy \(S=\left\{\dfrac{1+\sqrt{3}}{2};\dfrac{1-\sqrt{3}}{2}\right\}\)

Answer 2

=>2x-1=căn 3 hoặc 2x-1=-căn 3

=>2x=căn 3+1 hoặc 2x=-căn3+1

=>\(x=\dfrac{1\pm\sqrt{3}}{2}\)

Answer 3

`<=> 2x - 1 = +-sqrt 3`

`<=> 2x = +-sqrt3 + 1`

`<=> x = (+-sqrt3+1)/2`