tìm x (x-1)^2=1/4 3/2 *x-1=x-1/2 5/6-3x=-2/3+1/2 *x mong được giúp đỡ mình sẽ cho 5 sao nếu chi tiết

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1. `a) (x – 1)^2 = 1/4`

   $\text { ⇒ \(\left[ \begin{array}{l}x – 1 = \frac{1}{2} \\x – 1 = \frac{-1}{2}\end{array} \right.\) }$

   $\text { ⇒ \(\left[ \begin{array}{l}x = \frac{1}{2} + 1 \\x = \frac{-1}{2} + 1\end{array} \right.\) }$

   $\text { ⇒ \(\left[ \begin{array}{l}x = \frac{1}{2} + \frac{2}{2} \\x = \frac{-1}{2} + \frac{2}{2}\end{array} \right.\) }$

   $\text { ⇒ \(\left[ \begin{array}{l}x = \frac{3}{2} \\x = \frac{1}{2} \end{array} \right.\) }$

   $\text { Vậy x ∈ { $\frac{3}{2}$ ; $\frac{1}{2}$ } }$

   `b) 3/2 . x – 1 = x – 1/2`

   `⇒ 3/2 . x – x = – 1/2 + 1`   (áp dụng quy tắc chuyển vế)

   `⇒ ( 3/2 – 1) . x = – 1/2 + 2/2`

   `⇒ ( 3/2 – 2/2 ) . x = 1/2`

   `⇒  1/2 . x = 1/2`

   `⇒  x = 1/2 : 1/2`

   `⇒  x = 1`

   $\text { Vậy x = 1 }$

     

   `c) 5/6 – 3x = (-2)/3 + 1/2 . x`

   `⇒ 5/6 + 2/3 = 1/2 . x + 3x`  (áp dụng quy tắc chuyển vế) 

   `⇒ 5/6 + 4/6 = x . ( 1/2 + 3 )`

   `⇒  9/6 = x . ( 1/2 + 6/2 )`

   `⇒  9/6 = x . 7/2`

   `⇒  x = 9/6 : 7/2`

   `⇒  x = 9/6 . 2/7`

   `⇒  x = 3/7`

   $\text { Vậy x = $\frac{3}{7}$ }$

    

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2. 1, (x – 1)² = $\frac{1}{4}$

   (x – 1)² = $\frac{1}{2}$²

   ⇒ \(\left[ \begin{array}{l}x-1=\frac{1}{2}\\x-1=\frac{-1}{2} \end{array} \right.\) 

   ⇒ \(\left[ \begin{array}{l}x=\frac{1}{2}+1\\x=\frac{-1}{2}+1\end{array} \right.\) 

   ⇒ \(\left[ \begin{array}{l}x=\frac{1+2}{2}=\frac{3}{2}\\x=\frac{-1+2}{2}=\frac{1}{2}\end{array} \right.\) 

   2, $\frac{3}{2}$ x – 1 = x – $\frac{1}{2}$

   $\frac{3}{2}$ x – x = $\frac{-1}{2}$ + 1

   ($\frac{3}{2}$ – 1) x = $\frac{-1+2}{2}$

   ($\frac{3-2}{2}$) x = $\frac{1}{2}$

   $\frac{1}{2}$ x = $\frac{1}{2}$

   x = $\frac{1}{2}$ : $\frac{1}{2}$

   x = 1

   3, $\frac{5}{6}$ – 3x = $\frac{-2}{3}$ + $\frac{1}{2}$ x

   -3x – $\frac{1}{2}$ x = $\frac{-2}{3}$ – $\frac{5}{6}$

   (-3 – $\frac{1}{2}$) x = $\frac{-4-5}{6}$

   ($\frac{-6-1}{2}$) x = $\frac{-9}{6}$

   $\frac{-7}{2}$ x = $\frac{-9}{6}$ 

   x = $\frac{-9}{6}$ : $\frac{-7}{2}$

   x =  $\frac{-9}{6}$ . $\frac{-2}{7}$

   x = $\frac{3}{7}$

   Chúc bạn học tốt ^^

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