` \sqrt{4(1 - x)^{2}} - \sqrt{3} = 0 `
` <=> \sqrt{4(1 - x)^{2}} = \sqrt{3} `
` <=> 4(1 - x)^{2} = 3 `
` <=> (1 - x)^{2} = 3/4 `
` <=> 1 - x = ± \frac{\sqrt{3}}{2} `
` <=> ` \(\left[ \begin{array}{l}x_1=1-\frac{\sqrt{3}}{2}\\x_2=1+\frac{\sqrt{3}}{2}\end{array} \right.\)
Vậy ` S = {1 - \frac{\sqrt{3}}{2} ; 1 + \frac{\sqrt{3}}{2}} `