K
Khách

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

21 tháng 7 2015

=> x+3/4 =x hoặc x+3/4 = -x

=> 0 = 3/4 ( loại ) hoặc 2x = 3/4

=> x = 3/4 :2 = 3/8

1 tháng 1 2017

\(\frac{x-3}{2013}+\frac{x-4}{2012}=\frac{x-5}{2011}+\frac{x-6}{2010}\)

\(\Leftrightarrow\frac{x-3-2013}{2013}+\frac{x-2-2012}{2012}=\frac{x-5-2011}{2011}+\frac{x-6-2010}{2010}\)(mỗi vế trừ đi 2)

\(\Leftrightarrow\frac{x-2016}{2013}+\frac{x-2016}{2012}-\frac{x-2016}{2011}-\frac{x-2016}{2010}=0\)

\(\Leftrightarrow\left(x-2016\right)\left(\frac{1}{2013}+\frac{1}{2012}-\frac{1}{2011}-\frac{1}{2010}\right)=0\)

Mà \(\frac{1}{2013}+\frac{1}{2012}-\frac{1}{2011}-\frac{1}{2010}\ne0\)

\(\Rightarrow x-2016=0\Leftrightarrow x=2016\)

5 tháng 10 2019

Cộng mỗi vế cho 1 

Ta có: \(\frac{x-3-2013}{2013}+\frac{x-4-2012}{2012}=\frac{x-5-2011}{2011}+\frac{x-6-2010}{2010}\)

\(=>\left(\frac{x-2016}{2013}+\frac{x-2016}{2012}\right)-\left(\frac{x-2016}{2011}+\frac{x-2016}{2010}\right)=0\)

\(=>\left(x-2016\right).\left(\frac{1}{2013}+\frac{1}{2012}+\frac{1}{2011}+\frac{1}{2010}\right)\)

Mà \(\frac{1}{2013}+\frac{1}{2012}+\frac{1}{2011}+\frac{1}{2010}\ne0\)

\(=>x-2016=0\\ =>x=2016\)

10 tháng 10 2015

\(\frac{x+4}{2000}+\frac{x+3}{2001}=\frac{x+2}{2002}+\frac{x+1}{2003}\)

\(\Rightarrow\left(\frac{x+4}{2000}+1\right)+\left(\frac{x+3}{2001}+1\right)=\left(\frac{x+2}{2002}+1\right)+\left(\frac{x+1}{2003}+1\right)\)

\(\frac{x+2004}{2000}+\frac{x+2004}{2001}=\frac{x+2004}{2002}+\frac{x+2004}{2003}\)

\(\frac{x+2004}{2000}+\frac{x+2004}{2001}-\frac{x+2004}{2002}-\frac{x+2004}{2003}=0\)

\(\left(x+2004\right).\left(\frac{1}{2000}+\frac{1}{2001}-\frac{1}{2002}-\frac{1}{2003}\right)=0\)

Vì \(\frac{1}{2000}+\frac{1}{2001}-\frac{1}{2002}-\frac{1}{2003}\ne0\)

\(\Rightarrow x+2004=0\)

\(x=0-2004\)

\(x=-2004\)

10 tháng 1 2016

Ta có : \(\frac{x+2}{198}+\frac{x+3}{197}=\frac{x+4}{196}+\frac{x+5}{195}\)

=> \(\left(\frac{x+2}{198}+1\right)+\left(\frac{x+3}{197}+1\right)=\left(\frac{x+4}{196}+1\right)+\left(\frac{x+5}{195}+1\right)\)

=> \(\frac{x+2+198}{198}+\frac{x+3+197}{197}=\frac{x+4+196}{196}+\frac{x+5+195}{195}\)

=> \(\frac{x+200}{198}+\frac{x+200}{197}=\frac{x+200}{196}+\frac{x+200}{195}\)

=> \(\frac{x+200}{198}+\frac{x+200}{197}-\frac{x+200}{196}-\frac{x+200}{195}=0\)

=> \(\left(x+200\right)\left(\frac{1}{198}+\frac{1}{197}-\frac{1}{196}-\frac{1}{195}\right)=0\)

Ta có : \(\frac{1}{198}+\frac{1}{197}\ne\frac{1}{196}+\frac{1}{195}\)  =>    \(\frac{1}{198}+\frac{1}{197}-\frac{1}{196}-\frac{1}{195}\ne0\)

=> x + 200 = 0

=> x = -200

10 tháng 1 2016

<=> (\(\frac{x+2}{198}\)+1) +(\(\frac{x+3}{197}\)+1) =(\(\frac{x+4}{196}\)+1) +(\(\frac{x+5}{195}\)+1)

<=> \(\frac{x+200}{198}+\frac{x+200}{197}=\frac{x+200}{196}+\frac{x+200}{195}\)

<=> \(\frac{x+200}{198}+\frac{x+200}{197}-\frac{x+200}{196}-\frac{x+200}{195}=0\)

<=> \(\left(x+200\right)\cdot\left(\frac{1}{198}+\frac{1}{197}-\frac{1}{196}-\frac{1}{195}\right)\)=0

Vì \(\frac{1}{195}>\frac{1}{196}>\frac{1}{197}>\frac{1}{198}\)

<=> \(\frac{1}{198}+\frac{1}{197}-\frac{1}{196}-\frac{1}{195}\) khác 0

<=> \(x+200=0\)

<=> x       = 

14 tháng 11 2017

a) x = 6 ; y = 15.

x = -6 ; y = -15.

b) x = 2 ; y = 2.

x = -2 ; y = -2.

9 tháng 11 2016

a) \(\frac{x-1}{2009}+\frac{x-2}{2008}=\frac{x-3}{2007}+\frac{x-4}{2006}\)

<=> \(\left(\frac{x-1}{2009}-1\right)+\left(\frac{x-2}{2008}-1\right)-\left(\frac{x-3}{2007}-1\right)-\left(\frac{x-4}{2006}-1\right)=0\)

<=> \(\frac{x-2010}{2009}+\frac{x-2010}{2008}-\frac{x-2010}{2007}-\frac{x-2010}{2006}=0\)

<=> \(\left(x-2010\right)\left(\frac{1}{2009}+\frac{1}{2008}-\frac{1}{2007}-\frac{1}{2006}\right)=0\)

<=> x - 2010 = 0 Vì \(\frac{1}{2009}+\frac{1}{2008}-\frac{1}{2007}-\frac{1}{2006}\ne0\)

<=> x = 2010

14 tháng 4 2017

=> x-1 +x-2+X-3 = 4(x-4) => 3x-6 = 4x -16 nhé bạn

31 tháng 1 2020

Ta có :\(\frac{3}{x}+\frac{4}{y}+\frac{5}{z}=6\)

\(\Leftrightarrow\frac{6}{2x}+\frac{12}{3y}+\frac{20}{4z}=6\)

\(\Leftrightarrow\frac{6}{2x}+\frac{12}{2x}+\frac{20}{2x}=6\)

\(\Leftrightarrow\frac{6+12+20}{2x}=6\)

\(\Leftrightarrow\frac{19}{x}=6\)

\(\Leftrightarrow x=\frac{19}{6}\)

\(\Leftrightarrow\frac{2}{3}x=\frac{2}{3}.\frac{19}{6}=\frac{19}{9}=y\)

\(\Leftrightarrow\frac{3}{4}y=\frac{3}{4}.\frac{19}{9}=\frac{19}{12}=z\)

Vậy \(\hept{\begin{cases}x=\frac{19}{6}\\y=\frac{19}{9}\\z=\frac{19}{12}\end{cases}}\)