K
Khách

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

15 tháng 5 2021

\(\frac{x-2003}{16}+\frac{x-1997}{11}+\frac{x-1992}{9}+\frac{x-1991}{7}=10\)

\(\left(\frac{x-2003}{16}-1\right)+\left(\frac{x-1997}{11}-2\right)+\left(\frac{x-1992}{9}-3\right)+\left(\frac{x-1991}{7}-4\right)=10-1-2-3-4\)

\(\frac{x-2003-16}{16}+\frac{x-1997-22}{11}+\frac{x-1992-27}{9}+\frac{x-1991-21}{7}=10-10\)

\(\frac{x-2019}{16}+\frac{x-2019}{11}+\frac{x-2019}{9}+\frac{x-2019}{7}=0\)

\(\left(x-2019\right)\left(\frac{1}{16}+\frac{1}{11}+\frac{1}{9}+\frac{1}{7}\right)=0\)

\(\Rightarrow x-2019=0\left(\text{vì }\frac{1}{16}+\frac{1}{11}+\frac{1}{9}+\frac{1}{7}\ne0\right)\)

\(x=0+2019\)

\(x=2019\)

11 tháng 3 2023

`(x-2003)/16 +(x-1997)/11 +(x-1992)/9 +(x-1991)/7=10`

`<=>((x-2003)/16-1)+((x-1997)/11-2)+((x-1992)/9-3)+((x-1991)/7-4)=0`

`<=>(x-2019)/16+ (x-2019)/11 +(x-2019)/9+(x-2019)/7 =0`

`<=> (x-2019)(1/16+1/11+1/9+1/7)=0`

<=> x-2019=0`

`<=> x=2019`

11 tháng 3 2023

2 tháng 4 2020

\(\frac{x+1}{2003}+\frac{x+3}{2001}+\frac{x+5}{1999}=\frac{x+7}{1997}+\frac{x+9}{1995}+\frac{x+11}{1993}\)

\(\Leftrightarrow\frac{x+1}{2003}+1+\frac{x+3}{2001}+1+\frac{x+5}{1999}+1=\frac{x+7}{1997}+1+\frac{x+9}{1995}+1+\frac{x+11}{1993}+1\)

\(\Leftrightarrow\frac{x+2004}{2003}+\frac{x+2004}{2001}+\frac{x+2004}{1999}=\frac{x+2004}{1997}+\frac{x+2004}{1995}+\frac{x+2004}{1993}\)

\(\Leftrightarrow\frac{x+2004}{2003}+\frac{x+2004}{2001}+\frac{x+2004}{1999}-\frac{x+2004}{1997}-\frac{x+2004}{1995}-\frac{x+2004}{1993}=0\)

\(\Leftrightarrow\left(x+2004\right)\left(\frac{1}{2003}+\frac{1}{2001}+\frac{1}{1999}+\frac{1}{1997}+\frac{1}{1995}+\frac{1}{1993}\right)=0\)

\(\Leftrightarrow x+2004=0\) ( do \(\frac{1}{2003}+\frac{1}{2001}+\frac{1}{1999}+\frac{1}{1997}+\frac{1}{1995}+\frac{1}{1993}\ne0\))

\(\Leftrightarrow x=-2004\)

2 tháng 4 2020

\(\frac{x+1}{2003}\)\(+\)\(\frac{x+3}{2001}\)\(+\)\(\frac{x+5}{1999}\)\(\frac{x+7}{1997}\)\(+\frac{x+9}{1995}\)\(+\frac{x+11}{1993}\)

\(\Leftrightarrow\)\(\frac{x+1}{2003}\)\(+1+\)\(\frac{x+3}{2001}\)\(+1+\frac{x+5}{1999}\)\(\frac{x+7}{1997}\)\(+1+\frac{x+9}{1995}\)\(+1+\frac{x+11}{1993}\)

\(\Leftrightarrow\frac{x+2004}{2003}\)\(+\frac{x+2004}{2001}\)\(+\frac{x+2004}{1999}\)\(-\frac{x+2004}{1997}\)\(-\frac{x+2004}{1995}\)\(-\frac{x+2004}{1993}\)\(=0\)

\(\Leftrightarrow\left(x+2004\right)\left(\frac{1}{2003}+\frac{1}{2001}+\frac{1}{1999}-\frac{1}{1997}-\frac{1}{1995}-\frac{1}{1993}\right)=0\)

\(\Leftrightarrow x+2004=0\)(vì tích kia có kết quả khác 0)

\(\Leftrightarrow x=-2004\)

Vậy PT có tập nghiệm S = {-2004}

26 tháng 6 2020

cung dc bạn

26 tháng 6 2020

nếu được bạn giải thich giúp mình

1 tháng 4 2020

cái cuối là =-4 nhé!

1 tháng 4 2020

\(\frac{x+2001}{5}+\frac{x+1999}{7}+\frac{x+1997}{9}+\frac{x+1995}{11}=-4\)

\(\Rightarrow\frac{x+2001}{5}+1+\frac{x+1999}{7}+1+\frac{x+1997}{9}+1+\frac{x+1995}{11}+1=0\)

\(\Rightarrow\frac{x+2006}{5}+\frac{x+2006}{7}+\frac{x+2006}{9}+\frac{x+2006}{11}=0\)

\(\Rightarrow\left(x+2006\right)\left(\frac{1}{5}+\frac{1}{7}+\frac{1}{9}+\frac{1}{11}\right)=0\)

\(\Rightarrow x+2006=0\)vì \(\frac{1}{5}+\frac{1}{7}+\frac{1}{9}+\frac{1}{11}>0\)

\(\Rightarrow x=-2006\)

27 tháng 2 2020

Ta có : \(\frac{x-1991}{9}+\frac{x-1993}{7}+\frac{x-1995}{5}+\frac{x-1997}{3}+\frac{x-1999}{1}\)\(=\frac{x-9}{1991}+\frac{x-7}{1993}+\frac{x-5}{1995}+\frac{x-3}{1997}+\frac{x-1}{1999}\)

\(\Rightarrow\left(\frac{x-1991}{9}-1\right)+\left(\frac{x-1993}{7}-1\right)+\left(\frac{x-1995}{5}-1\right)+\left(\frac{x-1997}{3}-1\right)+\left(\frac{x-1999}{1}-1\right)\)

\(=\left(\frac{x-9}{1991}-1\right)+\left(\frac{x-7}{1993}-1\right)+\left(\frac{x-5}{1995}-1\right)+\left(\frac{x-3}{1997}-1\right)+\left(\frac{x-1}{1999}\right)\)

\(\Rightarrow\frac{x-2000}{9}+\frac{x-2000}{7}+\frac{x-2000}{5}+\frac{x-2000}{3}\)

\(=\frac{x-2000}{1991}+\frac{x-2000}{1993}+\frac{x-2000}{1995}+\frac{x-2000}{1997}+\frac{x-2000}{1999}\)

\(\Rightarrow\left(x-2000\right)\left(\frac{1}{9}+\frac{1}{7}+\frac{1}{5}+\frac{1}{3}\right)=\left(x-2000\right)\left(\frac{1}{1991}+\frac{1}{1993}+\frac{1}{1995}+\frac{1}{1997}+\frac{1}{1999}\right)\)

\(\Rightarrow\left(x-2000\right)\left(\frac{1}{9}+\frac{1}{7}+\frac{1}{5}+\frac{1}{3}\right)-\left(x-2000\right)\left(\frac{1}{1991}+\frac{1}{1993}+\frac{1}{1995}+\frac{1}{1997}+\frac{1}{1999}\right)=0\)

\(\Rightarrow\left(x-2000\right)\left[\left(\frac{1}{9}+\frac{1}{7}+\frac{1}{5}+\frac{1}{3}\right)-\left(\frac{1}{1991}+\frac{1}{1993}+\frac{1}{1995}+\frac{1}{1997}+\frac{1}{1999}\right)\right]=0\)

Vì \(\left(\frac{1}{9}+\frac{1}{7}+\frac{1}{5}+\frac{1}{3}\right)-\left(\frac{1}{1991}+\frac{1}{1993}+\frac{1}{1995}+\frac{1}{1997}+\frac{1}{1999}\right)\ne0\)

=> x - 2000 = 0 

=> x = 2000

19 tháng 3 2017

\(\frac{8}{x-8}+\frac{11}{x-11}=\frac{9}{x-9}+\frac{10}{x-10}\)<=>  \(\frac{8}{x-8}+1+\frac{11}{x-11}+1=\frac{9}{x-9}+1+\frac{10}{x-10}+1\)

<=>\(\frac{8+x-8}{x-8}+\frac{11+x-11}{x-11}=\frac{9+x-9}{x-9}+\frac{10+x-10}{x-10}\)

<=>\(\frac{x}{x-8}+\frac{x}{x-11}=\frac{x}{x-9}+\frac{x}{x-10}\)

<=>\(\frac{x}{x-8}+\frac{x}{x-11}-\frac{x}{x-9}-\frac{x}{x-10}=0\)

<=>\(x\left(\frac{1}{x-8}+\frac{1}{x-11}-\frac{1}{x-9}-\frac{1}{x-10}\right)=0\)

=>\(\orbr{\begin{cases}x=0\\\frac{1}{x-8}+\frac{1}{x-11}-\frac{x}{x-9}-\frac{x}{x-10}=0\end{cases}}\)

đến đoạn bạn giải tiếp nhé

7 tháng 9 2016

a.\(\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}=\frac{x+1}{13}+\frac{x+1}{14}\Rightarrow\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}-\frac{x+1}{13}-\frac{x+1}{14}=0\)

\(\Rightarrow\left(x+1\right)\left(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\right)=0\)

Mà: \(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\ne0\Rightarrow x+1=0\Rightarrow x=-1\)

b.

\(\frac{x+4}{1990}+\frac{x+3}{1991}=\frac{x+2}{1992}+\frac{x+1}{1993}\Rightarrow2+\frac{x+4}{1990}+\frac{x+3}{1991}=2+\frac{x+2}{1992}+\frac{x+1}{1993}\)

\(\Rightarrow\left(1+\frac{x+4}{1990}\right)+\left(1+\frac{x+3}{1991}\right)=\left(1+\frac{x+2}{1992}\right)+\left(1+\frac{x+1}{1993}\right)\)

\(\Rightarrow\frac{x+1994}{1990}+\frac{x+1994}{1991}=\frac{x+1994}{1992}+\frac{x+1994}{1993}\)

\(\Rightarrow\frac{x+1994}{1990}+\frac{x+1994}{1991}-\frac{x+1994}{1992}-\frac{x+1994}{1993}=0\)

\(\Rightarrow\left(x+1994\right)\left(\frac{1}{1990}+\frac{1}{1991}-\frac{1}{1992}-\frac{1}{1993}\right)=0\)

\(\frac{1}{1990}+\frac{1}{1991}-\frac{1}{1992}-\frac{1}{1993}\ne0\Rightarrow x+1994=0\Rightarrow x=-1994\)

Giải các phương trình sau : ( biến đổi đặc biệt )a) \(\frac{x+1}{35}\)+ \(\frac{x+3}{33}\)= \(\frac{x+5}{31}\)+ \(\frac{x+7}{29}\)( HD : cộng thêm 1 vào các hạng tử )b) \(\frac{x-10}{1994}\)+ \(\frac{x-8}{1996}\)+\(\frac{x-6}{1998}\)+ \(\frac{x-4}{2000}\)+ \(\frac{x-2}{2002}\)= \(\frac{x-2002}{2}\)+ \(\frac{x-2000}{4}\)+ \(\frac{x-1988}{6}\)+ \(\frac{x-1996}{8}\)+ \(\frac{x-1994}{10}\)( HD : trừ đi 1 vào các hạng tử...
Đọc tiếp

Giải các phương trình sau : ( biến đổi đặc biệt )

a) \(\frac{x+1}{35}\)\(\frac{x+3}{33}\)\(\frac{x+5}{31}\)\(\frac{x+7}{29}\)( HD : cộng thêm 1 vào các hạng tử )

b) \(\frac{x-10}{1994}\)\(\frac{x-8}{1996}\)+\(\frac{x-6}{1998}\)\(\frac{x-4}{2000}\)\(\frac{x-2}{2002}\)\(\frac{x-2002}{2}\)\(\frac{x-2000}{4}\)\(\frac{x-1988}{6}\)\(\frac{x-1996}{8}\)\(\frac{x-1994}{10}\)( HD : trừ đi 1 vào các hạng tử ) 

c) \(\frac{x-1991}{9}\)\(\frac{x-1993}{7}\)\(\frac{x-1995}{5}\)\(\frac{x-1997}{3}\)\(\frac{x-1991}{1}\)\(\frac{x-9}{1991}\)\(\frac{x-7}{1993}\)\(\frac{x-5}{1995}\)\(\frac{x-3}{1997}\)\(\frac{x-1}{1999}\)( HD : trừ đi 1 vào các hạng tử )

d) \(\frac{x-85}{15}\)\(\frac{x-74}{13}\)\(\frac{x-67}{11}\)\(\frac{x-64}{9}\)= 10  ( Chú ý : 10 = 1 + 2 + 3 + 4 )

e) \(\frac{x-1}{13}\)\(\frac{2x-13}{15}\)\(\frac{3x-15}{27}\)\(\frac{4x-27}{29}\)( HD : Thêm hoặc bớt 1 vào các hạng tử )

 

1
16 tháng 4 2020

a, \(\frac{x+1}{35}+\frac{x+3}{33}=\frac{x+5}{31}+\frac{x+7}{29}\)

\(\frac{x+36}{35}+\frac{x+36}{33}-\frac{x+36}{31}-\frac{x+36}{29}=0\)

\(\left(x+36\right)\left(\frac{1}{35}+\frac{1}{33}-\frac{1}{31}-\frac{1}{29}\right)=0\)

\(=>x+36=0\)

\(=>x=36\)