Tìm giá trị của x lớn hơn bằng -1/2 biết 3/5 căn bậc hai x+ 1/2 = 3/2

Ta có: \(\frac{3}{5}\sqrt {x + \frac{1}{2}} = \frac{3}{2}\)

\(\sqrt {x + \frac{1}{2}} = \frac{3}{2}:\frac{3}{5}\)

\(\sqrt {x + \frac{1}{2}} = \frac{3}{2}.\frac{5}{3}\)

\(\sqrt {x + \frac{1}{2}} = \frac{5}{2}\)

\({\left( {\sqrt {x + \frac{1}{2}} } \right)^2} = {\left( {\frac{5}{2}} \right)^2}\)

\(x + \frac{1}{2} = \frac{{25}}{4}\)

\(x = \frac{{25}}{4} - \frac{1}{2}\)

\(x = \frac{{23}}{4}\)

\(x = 5,75\).

Vậy \(x = 5,75\).