Answer

Câu `1:`

`(x + 1/2)^2 = 1/16`

`=> (x + 1/2)^2 = (+-1/4)^2`

`=> x + 1/2 = +-1/4`

`=>` $\left[\begin{matrix} x + \dfrac{1}{2} = \dfrac{1}{4}\\ x + \dfrac{1}{2} = \dfrac{-1}{4}\end{matrix}\right.$

`=>` $\left[\begin{matrix} x = \dfrac{1}{4} - \dfrac{1}{2}\\ x = \dfrac{-1}{4} - \dfrac{1}{2}\end{matrix}\right.$

`=>` $\left[\begin{matrix} x = \dfrac{-1}{4}\\ x = \dfrac{-3}{4}\end{matrix}\right.$

Vậy `x \in {-1/4 ; -3/4}`

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Câu `2:`

`(x + 1/3)^3 = {-1}/8`

`=> (x + 1/3)^3 = (-1/2)^3`

`=> x + 1/3 = -1/2`

`=> x = -1/2 - 1/3`

`=> x = -5/6`

Vậy `x = -5/6`

`=>` Chọn `bbB`

Câu `1`:

`(x+1/2)^2= 1/16`

`=> (x+1/2)^2= (±1/4)^2`

TH1: `x+1/2= 1/4`                        TH2: `x+1/2= -1/4`

   `=> x= -1/4`                                `=> x= -3/4`

Vậy `x∈{-1/4; -3/4}`

Câu `2`:

`(x+1/3)^3= -1/8`

`=> (x+1/3)^3= (-1/2)^3`

`=> x+1/3= -1/2`

`=> x= -5/6`

Vậy `x= -5/6`

`->` Chọn B