Question

Tìm x : (x + 1/2 )² = 1/16

Answer 1

\(\left(x+\frac{1}{2}\right)^2=\frac{1}{16}=\left(\frac{1}{4}\right)^2=\left(-\frac{1}{4}\right)^2\)

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

(+)  \(x+\frac{1}{2}=-\frac{1}{4}\Rightarrow x=-\frac{1}{4}-\frac{1}{2}=-\frac{3}{4}\)

Answer 2

\(\left(x+\frac{1}{2}\right)^2=\frac{1}{6}\)

\(\Rightarrow x+\frac{1}{2}\in\left\{\frac{1}{4};-\frac{1}{4}\right\}\)

\(\Rightarrow x\in\left\{-\frac{1}{4};-\frac{3}{4}\right\}\)