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9 tháng 11 2018

\(\frac{x-3}{x-1}=\frac{2017}{2016}\)

\(\Rightarrow2016\left(x-3\right)=2017\left(x-1\right)\)

\(\Rightarrow2016x-6048=2017x-2017\)

\(\Rightarrow2016x-2017x=2017+6048\)

\(\Rightarrow-x=8065\)

\(\Rightarrow x=-8065\)

3 tháng 3 2017

\(\frac{2016-x}{2017}\)+\(\frac{2017-x}{2016}\)+2=\(\frac{2016}{2017-x}\)+\(\frac{2017}{2016-x}\)+2

\(\frac{4033-x}{2017}\)+\(\frac{4033-x}{2016}\)=\(\frac{4033-x}{2017-x}\)+\(\frac{4033-x}{2016-x}\)

(4033-x)(\(\frac{1}{2017}\)+\(\frac{1}{2016}\)-\(\frac{1}{2017-x}\)-\(\frac{1}{2016-x}\))=0

=>\(\hept{\begin{cases}4033-x=0\\\frac{1}{2017}+\frac{1}{2016}-\frac{1}{2017-x}-\frac{1}{2016-x}\end{cases}}=0\)

=>x=4033

x=0

3 tháng 3 2017

mk ko biết xin lỗi bạn nha!!!

mk ko biết xin lỗi bạn nha!!!

mk ko biết xin lỗi bạn nha!!!

mk ko biết xin lỗi bạn nha!!!

8 tháng 7 2017

\(\frac{x+2015}{5}+\frac{x+2016}{4}=\frac{x+2017}{3}+\frac{x+2018}{2}\)

\(\Leftrightarrow\left(\frac{x+2015}{5}+1\right)+\left(\frac{x+2016}{4}+1\right)=\left(\frac{x+2017}{3}+1\right)+\left(\frac{x+2018}{2}+1\right)\)

\(\Leftrightarrow\frac{x+2020}{5}+\frac{x+2020}{4}-\frac{x+2020}{3}-\frac{x+2020}{2}=0\)

\(\Leftrightarrow\left(x+2020\right)\left(\frac{1}{5}+\frac{1}{4}-\frac{1}{3}-\frac{1}{2}\right)=0\)

\(\Leftrightarrow x+2020=0\)vì \(\frac{1}{5}+\frac{1}{4}+\frac{1}{3}+\frac{1}{2}\ne0\)

\(\Leftrightarrow x=-2020\)

1 tháng 8 2017

khó lắm

bây h thì bạn giải đc chưa

19 tháng 4 2019

đặt x-2016=a

y-2017=b

z-2018=c

ta có\(\frac{1}{\sqrt{a}}-\frac{1}{a}+\frac{1}{\sqrt{b}}-\frac{1}{b}+\frac{1}{\sqrt{c}}-\frac{1}{c}=\frac{3}{4}\)

=>\(\left(\frac{1}{\sqrt{a}}-\frac{1}{2}\right)^2+\left(\frac{1}{\sqrt{b}}-\frac{1}{2}\right)^2+\left(\frac{1}{\sqrt{c}}-\frac{1}{2}\right)^2=0\)

=>\(a=b=c=4\)

còn lại tự lm nốt

19 tháng 4 2019

oke cao van duc

thank nhiều nha

hok tốt

11 tháng 3 2019

\(\Leftrightarrow\frac{x-3}{2016}-1=\left(\frac{x-2}{2017}-1\right)+\left(\frac{x-1}{2018}-1\right)\)

\(\Leftrightarrow\frac{x-3-2016}{2016}=\frac{x-2-2017}{2017}+\frac{x-1-2018}{2018}\)

\(\Leftrightarrow\frac{x-2019}{2016}-\frac{x-2019}{2017}-\frac{x-2019}{2018}=0\)

\(\Leftrightarrow\left(x-2019\right)\left(\frac{1}{2016}-\frac{1}{2017}-\frac{1}{2018}\right)=0\)

\(\frac{1}{2016}-\frac{1}{2017}-\frac{1}{2018}\ne0\) ( không tin cứ bấm máy tính mà xem =)) )

\(\Rightarrow x-2019=0\Rightarrow x=2019\)

a) \(\frac{x+2015}{5}+\frac{x+2016}{4}=\frac{x+2017}{3}+\frac{x+2018}{2}\)

\(\Leftrightarrow\frac{x+2015}{5}+\frac{5}{5}+\frac{x+2016}{4}+\frac{4}{4}=\frac{x+2017}{3}+\frac{3}{3}+\frac{x+2018}{2}+\frac{2}{2}\)

\(\Leftrightarrow\frac{x+2020}{5}+\frac{x+2020}{4}=\frac{x+2020}{3}+\frac{x+2002}{2}\)

\(\frac{x+2020}{5}+\frac{x+2020}{4}-\frac{x+2020}{3}-\frac{x+2020}{2}=0\)

\(\Leftrightarrow\left(x+2020\right).\left(\frac{1}{5}+\frac{1}{4}-\frac{1}{3}-\frac{1}{2}\right)=0\)

\(\Leftrightarrow x+2020=0\)

\(\Leftrightarrow x=-2020\)

Vậy : \(x=-2020\)

Chúc bạn học tốt !!

13 tháng 8 2019

a) \(\frac{x+2015}{5}+\frac{x+2016}{4}=\frac{x+2017}{3}+\frac{x+2018}{2}\\ \left(\frac{x+2015}{5}+1\right)+\left(\frac{x+2016}{4}+1\right)=\left(\frac{x+2017}{3}+1\right)+\left(\frac{x+2018}{2}+1\right)\\ \frac{x+2020}{5}+\frac{x+2020}{4}=\frac{x+2020}{3}+\frac{x+2020}{2}\\ \frac{x+2020}{5}+\frac{x+2020}{4}-\frac{x+2020}{3}-\frac{x+2020}{2}=0\\ \left(x+2020\right)\left(\frac{1}{5}+\frac{1}{4}-\frac{1}{3}-\frac{1}{2}\right)=0\\ \Rightarrow x+2020=0\\ \Rightarrow x=-2020\)

Vậy x = -2020

b) \(\frac{x+2015}{5}+\frac{x+2016}{6}=\frac{x+2017}{7}+\frac{x+2018}{8}\\ \left(\frac{x+2015}{5}-1\right)+\left(\frac{x+2016}{6}-1\right)=\left(\frac{x+2017}{7}-1\right)+\left(\frac{x+2018}{8}-1\right)\\ \frac{x+2010}{5}+\frac{x+2010}{6}=\frac{x+2010}{7}+\frac{x+2010}{8}\\ \frac{x+2010}{5}+\frac{x+2010}{6}-\frac{x+2010}{7}-\frac{x+2010}{8}=0\\ \left(x+2010\right)\left(\frac{1}{5}+\frac{1}{6}-\frac{1}{7}-\frac{1}{8}\right)=0\\ \Rightarrow x+2010=0\\ \Rightarrow x=-2010\)

Vậy x = -2010

7 tháng 8 2018

help me

7 tháng 8 2018

\(a)\) Ta có : 

\(VP=\frac{2018}{1}+\frac{2017}{2}+\frac{2016}{3}+...+\frac{2}{2017}+\frac{1}{2018}\)

\(VP=\left(\frac{2018}{1}-1-...-1\right)+\left(\frac{2017}{2}+1\right)+\left(\frac{2016}{3}+1\right)+...+\left(\frac{2}{2017}+1\right)+\left(\frac{1}{2018}+1\right)\)

\(VP=1+\frac{2019}{2}+\frac{2019}{3}+...+\frac{2019}{2017}+\frac{2019}{2018}\)

\(VP=2019\left(\frac{1}{2}+\frac{1}{3}+...+\frac{1}{2017}+\frac{1}{2018}+\frac{1}{2019}\right)\)

Lại có : 

\(VT=\left(\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{2019}\right).x\)

\(\Rightarrow\)\(x=2019\)

Vậy \(x=2019\)

Chúc bạn học tốt ~ 

19 tháng 4 2020

Hình như đề sai dấu, mình sửa lại rồi!

\(\frac{x-1}{2017}+\frac{x-2}{2016}+\frac{x-3}{2015}+...+\frac{x-2017}{1}=2017\)

\(\Leftrightarrow\) \(\frac{x-1}{2017}-1+\frac{x-2}{2016}-1+\frac{x-3}{2015}-1+...+\frac{x-2017}{1}-1=0\)

\(\Leftrightarrow\) \(\frac{x-2018}{2017}+\frac{x-2018}{2016}+\frac{x-2018}{2015}+...+\frac{x-2018}{1}=0\)

\(\Leftrightarrow\) (x - 2018)\(\left(\frac{1}{2017}+\frac{1}{2016}+\frac{1}{2015}+...+1\right)=0\)

\(\Leftrightarrow\) x - 2018 = 0

\(\Leftrightarrow\) x = 2018

Vậy S = {2018}

Chúc bn học tốt!!

19 tháng 4 2020

Hình như đề sai dấu, mình sửa lại rồi!

\(\frac{x-1}{2017}+\frac{x-2}{2016}+\frac{x-3}{2015}+...+\frac{x-2017}{1}=2017\)

\(\Leftrightarrow\) \(\frac{x-1}{2017}-1+\frac{x-2}{2016}-1+\frac{x-3}{2015}-1+...+\frac{x-2017}{1}-1=0\)

\(\Leftrightarrow\) \(\frac{x-2018}{2017}+\frac{x-2018}{2016}+\frac{x-2018}{2015}+...+\frac{x-2018}{1}=0\)

\(\Leftrightarrow\) (x - 2018)\(\left(\frac{1}{2017}+\frac{1}{2016}+\frac{1}{2015}+...+1\right)=0\)

\(\Leftrightarrow\) x - 2018 = 0

\(\Leftrightarrow\) x = 2018

Vậy S = {2018}

Chúc bn học tốt!!

22 tháng 7 2018

\(\frac{x+4}{2016}+\frac{x+3}{2017}=\frac{x+2}{2018}+\frac{x+1}{2019}\)

\(\Rightarrow\frac{x+4}{2016}+1+\frac{x+3}{2017}+1=\frac{x+2}{2018}+1+\frac{x+1}{2019}+1\)

\(\Rightarrow\frac{x+4+2016}{2016}+\frac{x+3+2017}{2017}=\frac{x+2+2018}{2018}+\frac{x+1+2019}{2019}\)

\(\Rightarrow\frac{x+2020}{2016}+\frac{x+2020}{2017}=\frac{x+2020}{2018}+\frac{x+2020}{2019}\)

\(\Rightarrow\frac{x+2020}{2016}+\frac{x+2020}{2017}-\frac{x+2020}{2018}-\frac{x+2020}{2019}=0\)

\(\Rightarrow\left(x+2020\right)\left(\frac{1}{2016}+\frac{1}{2017}-\frac{1}{2018}-\frac{1}{2019}\right)=0\)

\(\Rightarrow x+2020=0\) vì \(\frac{1}{2016}+\frac{1}{2017}-\frac{1}{2018}-\frac{1}{2019}>0\)

\(\Rightarrow x=-2020\)