Tìm x , biết: b) trị tuyệt đối của( 2 x + 1/ 3 ) − √ 1 9 /16 = ( − √ 3/ 2 )^ 2 ;

b) \[\left| {2x + \frac{1}{3}} \right| - \sqrt {1\frac{9}{{16}}} = {\left( { - \frac{{\sqrt 3 }}{2}} \right)^2}\]

\[\left| {2x + \frac{1}{3}} \right| - \sqrt {\frac{{25}}{{16}}} = \frac{3}{4}\]

\[\left| {2x + \frac{1}{3}} \right| - \frac{5}{4} = \frac{3}{4}\]

\[\left| {2x + \frac{1}{3}} \right| = 2\]

TH1: \(2x + \frac{1}{3} = 2\)

\(2x = \frac{5}{3}\)

\(x = \frac{5}{6}\)

TH2: \(2x + \frac{1}{3} = - 2\)

\(2x = \frac{{ - 7}}{3}\)

\(x = \frac{{ - 7}}{6}\)

Vậy \(x \in \left\{ {\frac{5}{6};\frac{{ - 7}}{6}} \right\}\).