Đáp án + Giải thích các bước giải:
`a)`
`(x - 1/2)^2 = 1/9`
`⇔(x - 1/2)^2 = (±1/3)^2`
`⇔`\(\left[ \begin{array}{l}x-\dfrac{1}{2} =\dfrac{1}{3} \\x - \dfrac{1}{2} =\dfrac{-1}{3}\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x=\dfrac{5}{6}\\x=\dfrac{1}{6}\end{array} \right.\)
`b)`
`|x + 3| + 2 = 6`
`⇔ |x + 3| = 6 - 2`
`⇔|x + 3| = 4`
`⇔` \(\left[ \begin{array}{l}x + 3 = 4\\x + 3 = -4\end{array} \right.\)
`⇔` \(\left[ \begin{array}{l}x=1\\x=-7\end{array} \right.\)
