\(5.\left(x+2\right)^3+7=2\)
b,\(14-\left|\dfrac{3x}{2}-1\rig...">
K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

1 tháng 12 2021

\(a,5\left(x+2\right)^3+7=2\\ \Leftrightarrow5\left(x+2\right)^3=-5\\ \Leftrightarrow\left(x+2\right)^3=-1\\ \Leftrightarrow x+2=-1\\ \Leftrightarrow x=-3\\ b,14-\left|\dfrac{3}{2}x-1\right|=9\\ \Leftrightarrow\left|\dfrac{3}{2}x-1\right|=5\\ \Leftrightarrow\left[{}\begin{matrix}\dfrac{3}{2}x-1=5\\\dfrac{3}{2}x-1=-5\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}\dfrac{3}{2}x=6\\\dfrac{3}{2}x=-4\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=4\\x=-\dfrac{8}{3}\end{matrix}\right.\)

1 tháng 12 2021

\(a,\Leftrightarrow5\left(x+2\right)^3=-5\\ \Leftrightarrow\left(x+2\right)^3=-1\\ \Leftrightarrow x+2=-1\Leftrightarrow x=-3\\ b,\Leftrightarrow\left|\dfrac{3}{2}x-1\right|=5\Leftrightarrow\left[{}\begin{matrix}\dfrac{3}{2}x-1=5\\1-\dfrac{3}{2}x=5\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}\dfrac{3}{2}x=6\\\dfrac{3}{2}x=-4\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=4\\x=-\dfrac{8}{3}\end{matrix}\right.\)

27 tháng 7 2017

h) \(5^x+5^{x+2}=650\)

\(\Leftrightarrow5^x+5^x.5^2=650\)

\(\Leftrightarrow5^x\left(1+25\right)=650\)

\(\Leftrightarrow5^x.26=650\)

\(\Leftrightarrow5^x=25\)

\(\Leftrightarrow x=2\)

haizzz,đăng ít thôi,chứ nhìn hoa mắt quá =.=

1 tháng 8 2017

bây định làm j ở chỗ này vậy??? có j ib ns vs nhao chớ sao ns ở đây

24 tháng 7 2017

|2x-1|=1,5

TH(1)2x-1=1,5

2x =1,5+1

2x =2,5

x =2,5 :2

x =1,25

TH(2) 2x-1=-1,5

2x =-1,5+1

2x =-0,5

x =-0,5:2

x =-0,25

các câu khác cứ tương tự bạn nhé

24 tháng 7 2017

b) \(7,5-\left|5-2x\right|=-4,5\)

\(\left|5-2x\right|=7,5+4,7\)

\(\left|5-2x\right|=12\)

th1 :\(5-2x=12\)

\(2x=5-12\)

\(2x=-7\)

\(x=-7:2\)

\(x=-3,5\)

th2: \(5-2x=-12\)

\(2x=5+12\)

\(2x=17\)

\(x=17:2\)

\(x=8,5\)

c) \(-3+\left|x\right|=-1\)

\(\left|x\right|=-1+3\)

\(\left|x\right|=2\)

th1: \(x=-2\)

th2 : \(x=2\)

d)\(\left|2\dfrac{1}{3}-x\right|=\dfrac{1}{6}\)

\(\left|\dfrac{7}{3}-x\right|=\dfrac{1}{6}\)

th1 :\(\dfrac{7}{3}-x=\dfrac{1}{6}\)

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

\(x=\dfrac{11}{6}\)

th2: \(\dfrac{7}{3}-x=\dfrac{-1}{6}\)

\(x=\dfrac{7}{3}+\dfrac{1}{6}\)

\(x=\dfrac{-5}{2}\)

e) \(\dfrac{5}{7}-\left|x+1\right|=\dfrac{1}{14}\)

\(\left|x+1\right|=\dfrac{5}{7}-\dfrac{1}{14}\)

\(\left|x+1\right|=\dfrac{9}{14}\)

th1 :\(x+1=\dfrac{9}{14}\)

\(x=\dfrac{9}{14}-1\)

\(x=\dfrac{-5}{14}\)

th2 : \(x+1=\dfrac{-9}{14}\)

\(x=\dfrac{-9}{14}-1\)

\(x=\dfrac{-5}{14}\)

a: \(\Leftrightarrow\left(3x-2\right):\dfrac{7}{5}=\dfrac{17}{7}:\dfrac{13}{5}=\dfrac{85}{91}\)

\(\Leftrightarrow3x-2=\dfrac{85}{91}\cdot\dfrac{7}{5}=\dfrac{17}{13}\)

=>3x=43/13

hay x=43/39

b: \(\Leftrightarrow9x+207=121-8x\)

=>19x=-86

hay x=-86/19

c: \(\Leftrightarrow x^2-9=16\)

=>x2=25

=>x=5 hoặc x=-5

d: \(\Leftrightarrow\left|x\right|=\dfrac{1.64\cdot3.11}{8.51}\simeq0,6\)

=>x=0,6 hoặc x=-0,6

28 tháng 10 2018

a) \(\left[\left(\dfrac{3}{5}\right)^2-\left(\dfrac{2}{5}\right)^2\right]\cdot X=\left(\dfrac{1}{5}\right)^3\)

\(\left(\dfrac{3}{5}-\dfrac{2}{5}\right)\left(\dfrac{3}{5}+\dfrac{2}{5}\right)\cdot X=\dfrac{1}{125}\)

\(\dfrac{1}{5}\cdot1\cdot X=\dfrac{1}{125}\)

\(X=\dfrac{1}{125}:\dfrac{1}{5}=\dfrac{1}{25}\)

b) \(1\dfrac{2}{5}\cdot x+\dfrac{3}{7}=\dfrac{-4}{5}\)

\(1\dfrac{2}{5}\cdot x=\dfrac{-4}{5}-\dfrac{3}{7}\)

\(1\dfrac{2}{5}\cdot x=-\dfrac{43}{35}\)

\(x=-\dfrac{43}{35}:1\dfrac{2}{5}=-\dfrac{43}{49}\)

c) \(\left(3x-2\right)^2=9\)

*Nếu \(9=3^2\) thì:

\(3x-2=3\)

\(3x=5\Rightarrow x=\dfrac{5}{3}\)

*Nếu \(9=\left(-3\right)^2\) thì

\(3x-2=-3\)

\(3x=-1\Rightarrow x=-\dfrac{1}{3}\)

d) \(\left|x+\dfrac{1}{3}\right|-4=-1\)

\(\left|x+\dfrac{1}{3}\right|=3\)

\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{3}=3\\x+\dfrac{1}{3}=-3\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{8}{3}\\x=-\dfrac{10}{3}\end{matrix}\right.\)

Chúc bạn học giỏi.

28 tháng 10 2018

a)\(\dfrac{3^2-2^2}{5^2}.x=\dfrac{1}{5^3}\)

\(\Leftrightarrow\dfrac{5}{5^2}.x=\dfrac{1}{5^3}\)

\(\Leftrightarrow\dfrac{1}{5}.x=\dfrac{1}{5^3}\)

\(\Leftrightarrow x=\dfrac{1}{25}\)

b)\(\dfrac{7}{5}x+\dfrac{3}{7}=-\dfrac{4}{5}\)

\(\Leftrightarrow\dfrac{7}{5}x=-\dfrac{43}{35}\)

\(\Leftrightarrow x=\dfrac{-43}{49}\)

c)\(9x^2-12x+4=9\)

\(\Leftrightarrow9x^2-12x-5=0\)

\(\Leftrightarrow9x^2-15x+3x-5=0\)

\(\Leftrightarrow3x\left(3x-5\right)+3x-5=0\)

\(\Leftrightarrow\left(3x-5\right)\left(3x+1\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{5}{3}\\x=-\dfrac{1}{3}\end{matrix}\right.\)

d)\(\left|x+\dfrac{1}{3}\right|=3\)

\(\Leftrightarrow\left[{}\begin{matrix}x+\dfrac{1}{3}=3\\x+\dfrac{1}{3}=-3\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{8}{3}\\x=-\dfrac{10}{3}\end{matrix}\right.\)

27 tháng 11 2022

b: =>(3x-1)(3x+1)(2x+3)=0

hay \(x\in\left\{\dfrac{1}{3};-\dfrac{1}{3};-\dfrac{3}{2}\right\}\)

c: \(\Leftrightarrow\left|2x-\dfrac{1}{3}\right|=\dfrac{5}{6}+\dfrac{3}{4}=\dfrac{19}{12}\)

=>2x-1/3=19/12 hoặc 2x-1/3=-19/12

=>2x=23/12 hoặc 2x=-15/12=-5/4

=>x=23/24 hoặc x=-5/8

d: \(\Leftrightarrow-\dfrac{5}{6}\cdot x+\dfrac{3}{4}=-\dfrac{3}{4}\)

=>-5/6x=-3/2

=>x=3/2:5/6=3/2*6/5=18/10=9/5

e: =>2/5x-1/2=3/4 hoặc 2/5x-1/2=-3/4

=>2/5x=5/4 hoặc 2/5x=-1/4

=>x=5/4:2/5=25/8 hoặc x=-1/4:2/5=-1/4*5/2=-5/8

f: =>14x-21=9x+6

=>5x=27

=>x=27/5

h: =>(2/3)^2x+1=(2/3)^27

=>2x+1=27

=>x=13

i: =>5^3x*(2+5^2)=3375

=>5^3x=125

=>3x=3

=>x=1

8 tháng 10 2017

a. \(\dfrac{3}{4}-\left(2x-\dfrac{2}{3}\right)=\dfrac{-5}{6}\)

\(\Rightarrow2x-\dfrac{2}{3}=\dfrac{3}{4}-\dfrac{-5}{6}\)

\(\Rightarrow2x-\dfrac{2}{3}=\dfrac{19}{12}\)

\(\Rightarrow2x=\dfrac{19}{12}+\dfrac{2}{3}=\dfrac{9}{4}\)

\(\Rightarrow x=\dfrac{9}{4}:2=\dfrac{9}{8}\)

Vậy............

b. \(1,5-\left(x+\dfrac{7}{2}\right)=2^7:2^5\)

\(\Rightarrow1,5-\left(x+\dfrac{7}{2}\right)=2^2=4\)

\(\Rightarrow x+\dfrac{7}{2}=1,5-4=\dfrac{-5}{2}\)

\(\Rightarrow x=\dfrac{-5}{2}-\dfrac{7}{2}=-6\)

Vậy.............

11 tháng 12 2018

MÌNH GHI KẾT QUẢ THÔI NHÉ

A,2

b,\(\dfrac{-2}{3}\)hoặc2

c,\(\dfrac{13}{15}\)hoặc\(\dfrac{17}{-15}\)

11 tháng 12 2018

lm luôn đi bn

14 tháng 12 2018
https://i.imgur.com/KyG8gtS.jpg

a: \(\Leftrightarrow\left(\dfrac{12}{25}\right)^x=\dfrac{9}{25}-\dfrac{81}{625}=\dfrac{144}{625}\)

=>x=2

b: =>3x-1=-4

=>3x=-3

hay x=-1