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24 tháng 2 2020

\(\frac{x-971}{972}+\frac{x-973}{970}+\frac{x-975}{968}+\frac{x-977}{966}=\frac{x-972}{971}+\frac{x-970}{973}+\frac{x-968}{975}+\frac{x-966}{977}\)

\(\Rightarrow\frac{x-971}{972}-1+\frac{x-973}{970}-1+\frac{x-975}{968}-1+\frac{x-977}{966}-1=\frac{x-972}{971}-1+\frac{x-970}{973}-1+\frac{x-968}{975}-1+\frac{x-966}{977}-1\)\(\Rightarrow\frac{x-1943}{972}+\frac{x-1943}{970}+\frac{x-1943}{968}+\frac{x-1943}{966}=\frac{x-1943}{971}+\frac{x-1943}{973}+\frac{x-1943}{975}+\frac{x-966}{977}\)

\(\Leftrightarrow\frac{x-1943}{972}+\frac{x-1943}{970}+\frac{x-1943}{968}+\frac{x-1943}{966}-\frac{x-1943}{971}-\frac{x-1943}{973}-\frac{x-1943}{975}-\frac{x-966}{977}=0\)

\(\Leftrightarrow\left(x-1943\right).\left(\frac{1}{972}+\frac{1}{970}+\frac{1}{968}+\frac{1}{966}-\frac{1}{971}-\frac{1}{973}+\frac{1}{975}+\frac{1}{977}\right)=0\)

\(\Leftrightarrow\left(x-1943\right)=0\Leftrightarrow x=1943\)

Vậy...

8 tháng 7 2019

\(\frac{1954.0,24+76.19,54}{977.\left(x-4\right)}=2=>\frac{977.2.0,24+76.19,54}{977.\left(x-4\right)}=2\)

=> \(\frac{2.0,24+76.19,54}{x-4}=2\)

=> \(\frac{1485,52}{x-4}=2=>1485,52=\left(x-4\right).2\)

=> x - 4 = 1485,52 : 2

x - 4 =742,76

=> x = 742,76+4

=> x = 746,76

3 tháng 8 2019

Bạn ơi kết quả bài này cô mk đã chữa và = kết quả là 5 bn à.hihi

18 tháng 9 2018

1.

a. \(\frac{x}{y}=-\frac{3}{7}\Leftrightarrow\frac{x}{3}=\frac{-y}{7}\Leftrightarrow\frac{x}{3}=\frac{x+\left(-y\right)}{3+7}=\frac{x-y}{10}=-4\)

Bạn tự tính tiếp nhé ^^.

b. \(\frac{x}{3}=\frac{y}{12}=\frac{z}{5}\Rightarrow\left(\frac{x}{3}\right)^3=\frac{x}{3}.\frac{y}{12}.\frac{z}{5}=\frac{x.y.z}{3.12.5}=\frac{22,5}{180}=\frac{1}{8}\)

\(\frac{x^3}{27}=\frac{1}{8}\Rightarrow x^3=\left(27.8\right)=3^3.2^3=\left(3.2\right)^3\)

Đến đây bạn tìm được x rồi ^^

c.\(\hept{\begin{cases}\frac{x}{2}=\frac{y}{5}\\\frac{y}{5}=\frac{z}{3}\end{cases}\Rightarrow\frac{x}{2}=\frac{y}{5}=\frac{z}{3}=\frac{x+y+z}{2+5+3}=\frac{-970}{10}}\)

Đến đây bạn tính được rồi nhé! ^^

2. Bài 2 chỉ cần chuyển vế là ra : \(x+1=2\)

18 tháng 9 2018

a) ta có: \(\frac{x}{y}=\frac{-3}{7}\Rightarrow\frac{x}{-3}=\frac{y}{7}\)

ADTCDTSBN

...

b) ta có: \(\frac{x}{3}=\frac{y}{12}=\frac{z}{5}=k\Rightarrow\hept{\begin{cases}x=3k\\y=12k\\z=5k\end{cases}}\)

mà x.y.z = 22,5 => 3k.12k.5k = 22,5

                                  180.k3 = 22,5

                                         k3 = 1/8 = (1/2)3

=> k = 1/2

=> x = 3.1/2 = 3/2

y = 12.1/2 = 6

z = 5.1/2 = 5/2

KL:...

a) \(\sqrt{x}+928=968\Leftrightarrow\sqrt{x}=968-928=40=\sqrt{160}\Rightarrow x=160\)

b) \(\frac{x}{28}+\frac{91}{28}=\frac{100}{28}\Leftrightarrow x+91=100\Leftrightarrow x=100-91=9\)

c) \(\left(-x\right)+88=0\Leftrightarrow-x=0-88=-88\Leftrightarrow x=88\)

d) \(\sqrt{x+1}=4=\sqrt{16}\Leftrightarrow x+1=16\Leftrightarrow x=16-1=15\)

Cái j thek cậu, tuy tớ chưa nhìn phần sau nhưng mà tớ thây cậu bị đơ rồi.

\(40=\sqrt{160}\)

Cậu hc ở đâu cái này đấy Minh. 

9 tháng 3 2022

sửa đề đến đây thôi bạn nhé, do nếu thêm vào thì mình cũng ko biết có quy luật gì nữa :<

\(\dfrac{x-1}{99}-1+\dfrac{x-3}{97}-1+\dfrac{x-5}{95}-1=\dfrac{x-2}{98}-1+\dfrac{x-4}{96}-1\)

\(\Leftrightarrow\dfrac{x-100}{99}+\dfrac{x-100}{97}+\dfrac{x-100}{95}=\dfrac{x-100}{98}+\dfrac{x-100}{96}\)

\(\Leftrightarrow\left(x-100\right)\left(\dfrac{1}{99}+\dfrac{1}{97}+\dfrac{1}{95}-\dfrac{1}{98}-\dfrac{1}{96}\ne0\right)=0\Leftrightarrow x=100\)

 

NG
23 tháng 8 2023

a) 1 969, 1 970, 1 971, 1 972, 1 973, 1 974, 1 975.

b) 2, 4, 6, 8, 10, 12, 14.

c) 1, 3, 5, 7, 9, 11, 13, 15.

d) 5, 10, 15, 20, 25, 30, 35, 40.

3 tháng 3 2018

\(\frac{x}{6}+\frac{x}{10}+\frac{x}{15}+\frac{x}{21}+\frac{x}{28}+\frac{x}{36}+\frac{x}{45}+\frac{x}{55}+\frac{x}{66}+\frac{x}{78}+\frac{x}{78}=\frac{220}{39}\)

\(\Leftrightarrow x\left(\frac{1}{6}+\frac{1}{10}+\frac{1}{15}+\frac{1}{21}+\frac{1}{28}+\frac{1}{36}+\frac{1}{45}+\frac{1}{55}+\frac{1}{66}+\frac{1}{78}+\frac{1}{78}\right)=\frac{220}{39}\)

\(\Leftrightarrow x\cdot\frac{20}{39}=\frac{220}{39}\Rightarrow x=11\)

3 tháng 3 2018

\(\frac{x}{6}+\frac{x}{10}+\frac{x}{15}+\frac{x}{21}+\frac{x}{28}+\frac{x}{36}+\frac{x}{45}+\frac{x}{55}+\frac{x}{66}+\frac{x}{78}+\frac{x}{78}=\frac{220}{39}\)

\(=>x=\frac{1}{6}+\frac{1}{10}+\frac{1}{15}+\frac{1}{21}+\frac{1}{28}+\frac{1}{36}+\frac{1}{45}+\frac{1}{55}+\frac{1}{66}+\frac{1}{78}+\frac{1}{78}=\frac{220}{39}\)

\(x\cdot\frac{20}{39}=\frac{220}{39}\)

\(x=\frac{220}{39}:\frac{20}{39}=11\)

22 tháng 8 2020

1) Ta có : \(\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}=\frac{x+1}{13}+\frac{x+1}{14}\)

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

Vì \(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\ne0\)

=> x + 1 = 0

=> x = - 1

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

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

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

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

Vì \(\frac{1}{2006}+\frac{1}{2007}-\frac{1}{2008}-\frac{1}{2009}\ne0\)

=> x + 2010 = 0

=> x = -2010

c) \(\frac{x+1945}{45}+\frac{x+1954}{54}=\frac{x+1975}{75}+\frac{x+1969}{69}\)

\(\Rightarrow\left(\frac{x+1945}{45}-1\right)+\left(\frac{x+1954}{54}-1\right)=\left(\frac{x+1975}{75}-1\right)+\left(\frac{x+1969}{69}-1\right)\)

=> \(\frac{x+1900}{45}+\frac{x+1900}{54}=\frac{x+1900}{75}+\frac{x+1900}{69}\)

=> \(\left(x+1900\right)\left(\frac{1}{45}+\frac{1}{54}-\frac{1}{75}-\frac{1}{69}\right)=0\)

=> \(x+1900=0\left(\text{Vì }\frac{1}{45}+\frac{1}{54}-\frac{1}{75}-\frac{1}{69}\ne0\right)\)

=> x = -1900

d) \(\frac{x+2008}{10}+\frac{x+2010}{9}=\frac{x+2012}{8}+\frac{x+2014}{7}\)

=> \(\left(\frac{x+2008}{10}+2\right)+\left(\frac{x+2010}{9}+2\right)=\left(\frac{x+2012}{8}+2\right)+\left(\frac{x+2014}{7}+2\right)\)

=> \(\frac{x+2028}{10}+\frac{x+2028}{9}=\frac{x+2028}{8}+\frac{x+2028}{7}\)

=> \(\left(x+2028\right)\left(\frac{1}{10}+\frac{1}{9}-\frac{1}{8}-\frac{1}{7}\right)=0\)

=> x + 2028 = 0 \(\left(\text{Vì }\frac{1}{10}+\frac{1}{9}-\frac{1}{8}-\frac{1}{7}\ne0\right)\)

=> x = -2028

22 tháng 8 2020

1) Ta có: \(\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}=\frac{x+1}{13}+\frac{x+1}{14}\)

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

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

  + TH1\(x+1=0\)\(\Leftrightarrow\)\(x=-1\)

  + TH2\(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}=0\)

      Vì \(\hept{\begin{cases}\frac{1}{10}>\frac{1}{13}\\\frac{1}{11}>\frac{1}{14}\\\frac{1}{12}>0\end{cases}}\)\(\Rightarrow\)\(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}>\frac{1}{13}+\frac{1}{14}\)

            \(\Rightarrow\)\(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}>0\)

             mà \(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}=0\)

             \(\Rightarrow\)Phương trình trên vô nghiệm

Vậy \(x=-1\)

2) Ta có: \(\frac{x+4}{2006}+\frac{x+3}{2007}=\frac{x+2}{2008}+\frac{x+1}{2009}\)

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

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

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

  + TH1\(x+2010=0\)\(\Leftrightarrow\)\(x=-2010\)

  + TH2\(\frac{1}{2006}+\frac{1}{2007}-\frac{1}{2008}-\frac{1}{2009}=0\)

      Vì \(\hept{\begin{cases}\frac{1}{2006}>\frac{1}{2008}\\\frac{1}{2007}>\frac{1}{2009}\end{cases}}\)\(\Rightarrow\)\(\frac{1}{2006}+\frac{1}{2007}>\frac{1}{2008}+\frac{1}{2009}\)

              \(\Rightarrow\)\(\frac{1}{2006}+\frac{1}{2007}-\frac{1}{2008}-\frac{1}{2009}>0\)

               mà \(\frac{1}{2006}+\frac{1}{2007}-\frac{1}{2008}-\frac{1}{2009}=0\)

               \(\Rightarrow\)Phương trình trên vô nghiệm

Vậy \(x=-2010\)

3) Ta có: \(\frac{x+1945}{45}+\frac{x+1954}{54}=\frac{x+1975}{75}+\frac{x+1969}{69}\)

        \(\Leftrightarrow\left(\frac{x+1945}{45}-1\right)+\left(\frac{x+1954}{54}-1\right)-\left(\frac{x+1975}{75}-1\right)-\left(\frac{x+1969}{69}-1\right)=0\)

        \(\Leftrightarrow\frac{x+1900}{45}+\frac{x+1900}{54}-\frac{x+1900}{75}-\frac{x+1900}{69}=0\)

       \(\Leftrightarrow\left(x+1900\right).\left(\frac{1}{45}+\frac{1}{54}-\frac{1}{75}-\frac{1}{69}\right)=0\)

  

  + TH1\(x+1900=0\)\(\Leftrightarrow\)\(x=-1900\)

  + TH2\(\frac{1}{45}+\frac{1}{54}-\frac{1}{75}-\frac{1}{69}=0\)

      Vì \(\hept{\begin{cases}\frac{1}{45}>\frac{1}{75}\\\frac{1}{54}>\frac{1}{69}\end{cases}}\)\(\Rightarrow\)\(\frac{1}{45}+\frac{1}{54}>\frac{1}{75}+\frac{1}{69}\)

              \(\Rightarrow\)\(\frac{1}{45}+\frac{1}{54}-\frac{1}{75}-\frac{1}{69}>0\)

               mà \(\frac{1}{45}+\frac{1}{54}-\frac{1}{75}-\frac{1}{69}=0\)

               \(\Rightarrow\)Phương trình trên vô nghiệm

Vậy \(x=-1900\)

4) Ta có: \(\frac{x-99}{5}+\frac{x-97}{7}=\frac{x-95}{9}+\frac{x-93}{11}\)

         \(\Leftrightarrow\left(\frac{x-99}{5}-1\right)+\left(\frac{x-97}{7}-1\right)-\left(\frac{x-95}{9}-1\right)-\left(\frac{x-93}{11}-1\right)=0\)

         \(\Leftrightarrow\frac{x-104}{5}+\frac{x-104}{7}-\frac{x-104}{9}-\frac{x-104}{11}=0\)

         \(\Leftrightarrow\left(x-104\right).\left(\frac{1}{5}+\frac{1}{7}-\frac{1}{9}-\frac{1}{11}\right)=0\)

  

  + TH1\(x-104=0\)\(\Leftrightarrow\)\(x=104\)

  + TH2\(\frac{1}{5}+\frac{1}{7}-\frac{1}{9}-\frac{1}{11}=0\)

      Vì \(\hept{\begin{cases}\frac{1}{5}>\frac{1}{7}\\\frac{1}{9}>\frac{1}{11}\end{cases}}\)\(\Rightarrow\)\(\frac{1}{5}+\frac{1}{7}>\frac{1}{9}+\frac{1}{11}\)

              \(\Rightarrow\)\(\frac{1}{5}+\frac{1}{7}-\frac{1}{9}-\frac{1}{11}>0\)

               mà \(\frac{1}{5}+\frac{1}{7}-\frac{1}{9}-\frac{1}{11}=0\)

               \(\Rightarrow\)Phương trình trên vô nghiệm

Vậy \(x=104\)

5) Ta có: \(\frac{x+2008}{10}+\frac{x+2010}{9}=\frac{x+2012}{8}+\frac{x+2014}{7}\)

        \(\Leftrightarrow\left(\frac{x+2008}{10}+2\right)+\left(\frac{x+2010}{9}+2\right)-\left(\frac{x+2012}{8}+2\right)-\left(\frac{x+2014}{7}+2\right)=0\)

        \(\Leftrightarrow\frac{x+2028}{10}+\frac{x+2028}{9}-\frac{x+2028}{8}-\frac{x+2028}{7}=0\)

        \(\Leftrightarrow\left(x+2028\right).\left(\frac{1}{10}+\frac{1}{9}-\frac{1}{8}-\frac{1}{7}\right)=0\)

    + TH1\(x+2028=0\)\(\Leftrightarrow\)\(x=-2028\)

    + TH2\(\frac{1}{10}+\frac{1}{9}-\frac{1}{8}-\frac{1}{7}=0\)

      Vì \(\hept{\begin{cases}\frac{1}{10}< \frac{1}{8}\\\frac{1}{9}< \frac{1}{7}\end{cases}}\)\(\Rightarrow\)\(\frac{1}{10}+\frac{1}{9}< \frac{1}{8}+\frac{1}{7}\)

              \(\Rightarrow\)\(\frac{1}{10}+\frac{1}{9}-\frac{1}{8}-\frac{1}{7}< 0\)

               mà \(\frac{1}{10}+\frac{1}{9}-\frac{1}{8}-\frac{1}{7}=0\)

               \(\Rightarrow\)Phương trình trên vô nghiệm

Vậy \(x=-2028\)

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