Tìm x

a) | x - \(\dfrac{3}{2}\) | = \(\left(\dfrac{12}{13}+7\right)\) + \(\left(-8+\dfrac{1}{13}\right)\)

| x - \(\dfrac{3}{2}\) | = \(\dfrac{12}{13}+7-8+\dfrac{1}{13}\)

| x - \(\dfrac{3}{2}\) | = 1 + 7 - 8

=> | x - \(\dfrac{3}{2}\) | = 0

=> x - \(\dfrac{3}{2}\) = 0

=> x = \(\dfrac{3}{2}\)

b) ( \(\dfrac{3}{4}-\dfrac{1}{5}-\dfrac{1}{6}\) ) . \(\dfrac{1}{30}\) - | 3 . x - 3 | = 2

=> \(\dfrac{27}{4}\) . \(\dfrac{1}{30}\) - | 3x - 3 | = 2

=> \(\dfrac{9}{40}\) - | 3x - 3 | = 2

=> | 3x - 3 | = \(\dfrac{9}{40}\) - 2

=> | 3x - 3 | = \(\dfrac{-71}{40}\)

Th1 :

3x - 3 = \(\dfrac{-71}{40}\)

=> 3x = \(\dfrac{-71}{40}\) + 3

=> 3x = \(\dfrac{49}{40}\)

=> x = \(\dfrac{49}{40}\) : 3

=> x = \(\dfrac{49}{120}\)

TH2 :

3x - 3 = \(\dfrac{71}{40}\)

=> 3x = \(\dfrac{191}{40}\)

=> x = \(\dfrac{191}{120}\)

Vậy x = \(\dfrac{49}{120}\) hoặc \(\dfrac{191}{120}\)

a: =>|x-3/2|=12/13+1/13+7-8=0

=>x-3/2=0

hay x=3/2

b: \(\Leftrightarrow\dfrac{45-12-10}{60}\cdot\dfrac{1}{30}-\left|3x-3\right|=2\)

\(\Leftrightarrow\left|3x-3\right|=\dfrac{23}{60}\cdot\dfrac{1}{30}-2=-\dfrac{1777}{1800}\)(vô lý)

a, \(3\frac{12}{13}< x\frac{12}{13}< 5\frac{12}{13}\Rightarrow x=4\)

b, \(x\frac{3}{4}=\frac{21989}{7996}=\frac{11}{4}=2\frac{3}{4}\Rightarrow x=2\)

~ Hok tốt ~

Trả lời : 

a)x=4

b)x=2

\(\downarrow\)

a) \(\frac{561}{143}< x\frac{12}{13}< \frac{1463}{247}\)

\(\Rightarrow3\frac{12}{13}< x\frac{12}{13}< 5\frac{12}{13}\)

\(\Rightarrow x=4\)

b) \(x\frac{3}{4}=\frac{21989}{7996}\)

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

\(\Rightarrow x=2\)

~ Hok tốt ~

a) Ta có 8 5 = − 12 x => 8. x = -12 . 5 => x   =   − 15 2  ( KTM)

b) x 3 = 3 x => x .x = 3. 3 => x 2 = 9  => x = 3 hoặc x = -3

c) x = 4 hoặc x = -4

a) x = 4                

b) x = 3     

c) x = 2                

d) x = 1. 

a) x = -1.                      b) x = 4 hoặc x = 5.

c) x = ± 2 .                  d) x = 1 hoặc x = 2.