Tìm giá trị của (x > 0) biết:
Giải thích
Đáp án: 0,15
Ta có: \(\left| {2x + \frac{1}{5}} \right| = \frac{1}{2}\)
TH1: \(2x + \frac{1}{5} = \frac{1}{2}\)
\(2x = \frac{1}{2} - \frac{1}{5}\)
\(2x = \frac{3}{{10}}\)
\(x = \frac{3}{{10}}:2\)
\(x = \frac{3}{{10}}.\frac{1}{2}\)
\(x = \frac{3}{{20}}\)
\(x = 0,15\)
TH2: \(2x + \frac{1}{5} = - \frac{1}{2}\)
\(2x = - \frac{1}{2} - \frac{1}{5}\)
\(2x = - \frac{7}{{10}}\)
\(x = - \frac{7}{{10}}:2\)
\(x = - \frac{7}{{10}}.\frac{1}{2}\)
\(x = - \frac{7}{{20}}\)
\(x = - 0,35\)