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BC
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NH
16 tháng 7 2019 lúc 11:22

\(\frac{x+4}{2019}+\frac{x+3}{2020}=\frac{x+2}{2021}+\frac{x+1}{2020}\)

\(\Leftrightarrow(\frac{x+4}{2019}+1)+(\frac{x+3}{2020}+1)=(\frac{x+2}{2021}+1)+(\frac{x+1}{2022}+1)\)

\(\Leftrightarrow\frac{x+2023}{2019}+\frac{x+2023}{2020}=\frac{x+2023}{2021}+\frac{x+2023}{2022}\)

\(\Leftrightarrow\frac{x+2023}{2019}+\frac{x+2023}{2020}-\frac{x+2023}{2021}-\frac{x+2023}{2022}=0\)

\(\Leftrightarrow\left(x+2023\right)\left(\frac{1}{2019}+\frac{1}{2020}-\frac{1}{2021}-\frac{1}{2020}\right)=0\)

\(\Leftrightarrow x+2023=0\)

\(\Leftrightarrow x=-2023\)

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NH
16 tháng 7 2019 lúc 11:24

Nhầm đề :( Với bước thứ 4 sửa thành ( 1/2019 + 1/2020 - 1/2021 - 1/2022 ) 

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NN
16 tháng 7 2019 lúc 11:31

\(\frac{x+4}{2019}+\frac{x+3}{2020}=\frac{x+2}{2021}+\frac{x+1}{2022}\)

\(\Leftrightarrow\)\(\frac{x+4}{2019}+\frac{x+3}{2020}+2=\frac{x+2}{2021}+\frac{x+1}{2022}+2\)

\(\Leftrightarrow\)\(\left(\frac{x+4}{2019}+1\right)+\left(\frac{x+3}{2020}+1\right)=\left(\frac{x+2}{2021}+1\right)+\left(\frac{x+1}{2022}+1\right)\)

\(\Leftrightarrow\)\(\left(\frac{x+4}{2019}+\frac{2019}{2019}\right)+\left(\frac{x+3}{2020}+\frac{2020}{2020}\right)\)\(=\)\(\left(\frac{x+2}{2021}+\frac{2021}{2021}\right)+\left(\frac{x+1}{2022}+\frac{2022}{2022}\right)\)

\(\Leftrightarrow\)\(\frac{x+2023}{2019}+\frac{x+2023}{2020}=\frac{x+2023}{2021}+\frac{2023}{2022}\)

\(\Leftrightarrow\)\(\frac{x+2023}{2019}+\frac{x+2023}{2020}-\frac{x+2023}{2021}-\frac{x+2023}{2022}=0\)

\(\Leftrightarrow\) \(\left(x+2023\right).\left(\frac{1}{2019}+\frac{1}{2020}-\frac{1}{2021}-\frac{1}{2022}\right)=0\)

\(\Leftrightarrow\)\(x+2023=0\)      ( Vì \(\frac{1}{2019}+\frac{1}{2020}-\frac{1}{2021}-\frac{1}{2022}\ne0\))

\(\Leftrightarrow\)\(x=-2023\)

Vậy x = -2023

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NA
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PL
21 tháng 8 2019 lúc 13:08

\(x-2019+\frac{x-2020}{2}=\frac{x-2021}{3}+\frac{x-2022}{4}\)

\(\Rightarrow x-2019+1+\frac{x-2020}{2}+1=\frac{x-2021}{3}+1+\frac{x-2022}{4}+1\)

\(\Rightarrow x-2018+\frac{x-2020+2}{2}=\frac{x-2021+3}{3}+\frac{x-2022+4}{4}\)

\(\Rightarrow x-2018+\frac{x-2018}{2}-\frac{x-2018}{3}-\frac{x-2018}{4}=0\)

\(\Rightarrow\left(x-2018\right)\left(1-\frac{1}{2}-\frac{1}{3}-\frac{1}{4}\right)=0\)

\(\Rightarrow-\frac{1}{12}\left(x-2018\right)=0\Leftrightarrow x=2018\)

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H24
4 tháng 9 2020 lúc 17:36

               Bài làm :

Ta có :

\(x-2019+\frac{x-2020}{2}=\frac{x-2021}{3}+\frac{x-2022}{4}\)

\(\Rightarrow x-2019+1+\frac{x-2020}{2}+1=\frac{x-2021}{3}+1+\frac{x-2022}{4}+1\)

\(\Rightarrow x-2018+\frac{x-2020+2}{2}=\frac{x-2021+3}{3}+\frac{x-2022+4}{4}\)

\(\Rightarrow x-2018+\frac{x-2018}{2}-\frac{x-2018}{3}-\frac{x-2018}{4}=0\)

\(\Rightarrow\left(x-2018\right)\left(1-\frac{1}{2}-\frac{1}{3}-\frac{1}{4}\right)=0\)

\(\text{Vì : }\left(1-\frac{1}{2}-\frac{1}{3}-\frac{1}{4}\right)\ne0\Rightarrow x-2018=0\)

\(\Rightarrow x=2018\)

Vậy x=2018

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NA
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TN
3 tháng 1 2018 lúc 19:26

\(\frac{x-4}{2021}+\frac{x-3}{2020}=\frac{x-2}{2019}+\frac{x-1}{2018}\)

\(\Leftrightarrow\left(\frac{x-4}{2021}+1\right)+\left(\frac{x-3}{2020}+1\right)=\left(\frac{x-2}{2019}+1\right)+\left(\frac{x-1}{2018}+1\right)\)

\(\Leftrightarrow\frac{x+2017}{2021}+\frac{x+2017}{2020}=\frac{x+2017}{2019}+\frac{x+2017}{2018}\)

\(\Leftrightarrow\frac{x+2017}{2021}+\frac{x+2017}{2020}-\frac{x+2017}{2019}-\frac{x+2017}{2018}=0\)

\(\Leftrightarrow\left(x+2017\right)\left(\frac{1}{2021}+\frac{1}{2020}-\frac{1}{2019}-\frac{1}{2018}\right)=0\)

Mà \(\left(\frac{1}{2021}+\frac{1}{2020}-\frac{1}{2019}-\frac{1}{2018}\right)\ne0\)

\(\Leftrightarrow x+2017=0\)

\(\Leftrightarrow x=-2017\)

Vậy ..

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NQ
3 tháng 1 2018 lúc 19:23

=> (x-4/2021 +1) + (x-3/2020 +1) = (x-2/2019 +1)+ (x-1/2018 +1)

=> x+2017/2021 + x+2017/2020 = x+2017/2019 + x+2017/2018

=> x+2017/2018 + x+2017/2018 - x+2017/2020 - x+2017/2021 = 0

=> (x+2017).(1/2018+1/2019+1/2020+1/2021) = 0

=> x+2017 = 0 ( vì 1/2018+1/2019+1/2020+1/2021 > 0 )

=> x=-2017

Vậy x=-2017

k mk nha

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TD
3 tháng 1 2018 lúc 19:28

\(\frac{x-4}{2021}+\frac{x-3}{2020}=\frac{x-2}{2019}+\frac{x-1}{2018}\)

\(\left(\frac{x-4}{2021}+1\right)+\left(\frac{x-3}{2020}+1\right)=\left(\frac{x-2}{2019}+1\right)+\left(\frac{x-1}{2018}+1\right)\)

\(\frac{x-2017}{2021}+\frac{x-2017}{2020}=\frac{x-2017}{2019}+\frac{x-2017}{2018}\)

\(\frac{x-2017}{2021}+\frac{x-2017}{2020}-\frac{x-2017}{2019}-\frac{x-2017}{2018}=0\)

\(\left(x-2017\right).\left(\frac{1}{2021}+\frac{1}{2020}-\frac{1}{2019}-\frac{1}{2018}\right)=0\)

vì \(\frac{1}{2021}+\frac{1}{2020}-\frac{1}{2019}-\frac{1}{2018}\ne0\)nên x - 2017 = 0 \(\Rightarrow\)x = 2017

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H24
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TN
9 tháng 4 2020 lúc 14:21

\(\frac{x+1}{2018}+\frac{x+1}{2019}=\frac{x+1}{2020}+\frac{x+1}{2021}\Leftrightarrow\frac{x+1}{2018}+\frac{x+1}{2019}-\frac{x+1}{2020}-\frac{x+1}{2021}=0\)

\(\Leftrightarrow\left(x+1\right)\left(\frac{1}{2018}+\frac{1}{2019}-\frac{1}{2020}-\frac{1}{2021}\right)=0\Leftrightarrow x+1=0\Leftrightarrow x=-1\)

KL: ................

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TV
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ND
28 tháng 3 2019 lúc 10:52

\(\frac{x+1}{2018}+\frac{x+2}{2019}=\frac{x+3}{2020}+\frac{x+4}{2021}\)

\(\Leftrightarrow\left(\frac{x+1}{2018}-1\right)+\left(\frac{x+2}{2019}-1\right)=\left(\frac{x+3}{2020}-1\right)+\left(\frac{x+4}{2021}-1\right)\)

\(\Leftrightarrow\frac{x-2017}{2018}+\frac{x-2017}{2019}=\frac{x-2017}{2020}+\frac{x-2017}{2021}\)

\(\Leftrightarrow\left(x-2017\right)\left(\frac{1}{2018}+\frac{1}{2019}-\frac{1}{2020}-\frac{1}{2021}\right)=0\)

\(\Leftrightarrow x-2017=0\)\(\left(\frac{1}{2018}+\frac{1}{2019}-\frac{1}{2020}-\frac{1}{2021}\ne0\right)\)

\(\Leftrightarrow x=2017\)

Vậy \(S=\left\{2017\right\}\)

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TP
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LD
19 tháng 6 2017 lúc 7:10

Ta có : \(\frac{x-1}{2017}+\frac{x-2}{2018}-\frac{x-3}{2019}=\frac{x-4}{2020}\)

\(\Rightarrow\frac{x-1}{2017}+\frac{x-2}{2018}=\frac{x-4}{2020}+\frac{x-3}{2019}\)

\(\Rightarrow1+\frac{x-1}{2017}+1+\frac{x-2}{2018}=1+\frac{x-4}{2020}+1+\frac{x-3}{2019}\)

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

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

\(\Rightarrow\left(2016+x\right)\left(\frac{1}{2017}+\frac{1}{2018}-\frac{1}{2019}-\frac{1}{2020}\right)=0\)
\(\text{Mà : }\)\(\frac{1}{2017}+\frac{1}{2018}-\frac{1}{2019}-\frac{1}{2020}\ne0\)

\(\text{Nên : }\) \(2016+x=0\)

\(\Rightarrow x=-2016\)

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TP
1 tháng 1 2018 lúc 20:22

Giỏi wá!!!!!!!!

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OK
18 tháng 1 2019 lúc 15:45

Ta có : x−12017 +x−22018 −x−32019 =x−42020 

⇒x−12017 +x−22018 =x−42020 +x−32019 

⇒1+x−12017 +1+x−22018 =1+x−42020 +1+x−32019 

⇒2016+x2017 +2016+x2018 =2016+x2020 +2016+x2019 

⇒2016+x2017 +2016+x2018 −2016+x2019 −2016+x2020 =0

⇒(2016+x)(12017 +12018 −12019 −12020 )=0
Mà : 12017 +12018 −12019 −12020 ≠0

Nên : 2016+x=0

⇒x=−2016

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VA
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NH
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ND
25 tháng 2 2023 lúc 20:08

\(\dfrac{x-4}{2022}+\dfrac{x-3}{2021}+\dfrac{x-2}{2020}+\dfrac{x-1}{2019}\text{=}-4\)

\(\dfrac{x-4}{2022}+\dfrac{x-3}{2021}+\dfrac{x-2}{2020}+\dfrac{x-1}{2019}+4\text{=}0\)

\(\left(\dfrac{x-4}{2022}+1\right)+\left(\dfrac{x-3}{2021}+1\right)+\left(\dfrac{x-2}{2020}+1\right)+\left(\dfrac{x-1}{2019}+1\right)\text{=}0\)

\(\dfrac{x-2018}{2022}+\dfrac{x-2018}{2021}+\dfrac{x-2018}{2020}+\dfrac{x-2018}{2019}\text{=}0\)

\(\left(x-2018\right)\left(\dfrac{1}{2022}+\dfrac{1}{2021}+\dfrac{1}{2020}+\dfrac{1}{2019}\right)\text{=}0\)

\(Do:\) \(\dfrac{1}{2022}+\dfrac{1}{2021}+\dfrac{1}{2020}+\dfrac{1}{2019}\ne0\)

\(x-2018\text{=}0\)

\(x\text{=}2018\)

\(Vậy...\)

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H24
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JI
11 tháng 2 2020 lúc 20:26

1.Tìm điều kiện xác định của phương trình:

a) 1x2+1 -4xx =0 (1)

b) 1x21 -2020 (2)

c) x2020x2019 +

a) Dễ thấy: x2 + 1 ≠ 0 \(\forall\) x

Vậy điều kiện để phương trình (1) xác định là x ≠ 0.

b) Để phương trình (2) xác định thì x2 - 1 ≠ 0 ⇔ (x + 1)(x - 1) ≠ 0

\(\left[{}\begin{matrix}x+1\ne0\\x-1\ne0\end{matrix}\right.\) ⇔ x ≠ \(\pm\) 1

Vậy điều kiện để phương trình (2) xác định là x ≠ \(\pm\) 1.

c) Dễ thấy: x2 + 1 ≠ 0 \(\forall\) x

Vậy điều kiện để phương trình (3) xác định là x ≠ 2019.

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