(x+5687):7=3542+18754
2006:x+1955=2014
Tìm X:
2006 : X + 1955 = 2014; X x 35 - 35 = 1225; 981 x (X+189)=185409
2006 : \(x\) + 1955 = 2014
2006 : \(x\) = 2014 - 1955
2006 : \(x\) = 59
\(x\) = 2006 : 59
\(x\) = 34
\(x\times35\) - 35 = 1225
\(x\) \(\times\) 35 = 1225 + 35
\(x\times\) 35 = 1260
\(x\) = 1260 : 35
\(x\) = 36
981 \(\times\) ( \(x\) + 189) = 185409
\(x\) + 189 = 185409 : 981
\(x\) + 189 = 189
\(x\) = 189 - 189
\(x\) = 0
Tim x biết
a) 2006 | x - 1 | + 1 (x-1)^2 = 2005 | 1 -x |
b) (x -2014 )^2014 + ( y - 2015 )^2014 = 0
a/ \(2006.|x-1|+1.\left(x-1\right)^2=2005.|1-x|.\)
\(\Rightarrow2006.|x-1|+\left(x-1\right)^2-2005.|1-x|=0\)
Vì \(\hept{\begin{cases}|x-1|\ge0\\|1-x|\ge0\end{cases}}\)
mà \(|x-1|=x-1\)
\(|1-x|=x-1\)\(\Rightarrow|x-1|=|1-x|\)
Thay vào ta được:
\(2006.\left(x-1\right)+\left(x-1\right)^2-2005.\left(x-1\right)=0\)
\(\Rightarrow\left(x-1\right).\left(2006-2005\right)+\left(x-1\right)^2=0\)
\(\Rightarrow\left(x-1\right)+\left(x-1\right)^2=0\)
Vì \(\left(x-1\right)^2\ge0\)với mọi x
nên \(\Rightarrow\hept{\begin{cases}x-1=0\\\left(x-1\right)^2\end{cases}\Rightarrow\hept{\begin{cases}x=1\\x=1\end{cases}}}\)(t/m)
Vậy x = 1
b/ Vì \(\left(x-2014\right)^{2014}\ge0\)với mọi x
\(\left(y-2015\right)^{2014}\ge0\)với mọi y
Để \(\left(x-2014\right)^{2014}+\left(y-2015\right)^{2014}=0\)
\(\Rightarrow\hept{\begin{cases}\left(x-2014\right)^{2014}=0\\\left(y-2015\right)^{2014}=0\end{cases}}\)
\(\Rightarrow\hept{\begin{cases}x-2014=0\\y-2015=0\end{cases}}\)
\(\Rightarrow\hept{\begin{cases}x=2014\\y=2015\end{cases}}\)
Vậy : .......
Nhớ k nhé! Thank you!!!
x-67421=5687
1/2004 x (1- 1/2005) x (1- 1/2006)x ........x (1- 1/2014)
Trả lời:
\(\frac{1}{2004}\times\left(1-\frac{1}{2005}\right)\times\left(1-\frac{1}{2006}\right)\times...\times\left(1-\frac{1}{2014}\right)\)
\(=\frac{1}{2004}\times\frac{2004}{2005}\times\frac{2005}{2006}\times...\times\frac{2013}{2014}\)
\(=\frac{1}{2014}\)
= 2003/2004 x 2004/2005 x 2005/2006 x .... x 2013/2014
=
= 2003/2014
Chúc bạn học tốt!
tìm x, y ,z biết: |x-6| + |x-10| + | x-2012| + |y- 2014| + | z-2015| = 2006
Tìm x:
a, x : 4 = 1568
b, x × 2 = 1784
c, (x + 234) × 2 = 9872
d, (x – 48) : 4 = 5687
Tìm x:
a,456+( x - 357 ) = 1362
b, ( 2345 - x ) -183 = 2014
c, ( x - 2005 ) . 2006 = 0 ( dấu . là dấu nhân )
480 + 45 .4 = ( x + 125 ) : 5 +260
2005.( x - 2006 ) = 2005
[ ( x + 50) . 50 -50 ] : 50 = 50
456 + (x - 357) = 1362
=> x - 357 = 1362 - 456
=> x - 357 = 906
=> x = 906 + 357
=> x = 1263
c) (x - 2005) . 2006 = 0
=> x - 2005 = 0 : 2006
=> x - 2005 = 0
=> x = 0 + 2005
=> x = 2005
a) 456 + ( x - 357 ) = 1362
=> x - 357 = 906
=> x = 1263
b) ( 2345 - x ) - 183 = 2014
=> 2345 - x = 2197
=> x = 148
c) ( x - 2005 ) . 2006 = 0
=> x - 2005 = 0
=> x = 2005
còn lại làm tương tự
Giải phương trình
\(\frac{x-1}{2011}+\frac{x-2}{2012}+\frac{x-3}{2013}+\frac{x-4}{2014}=x+2006\)
\(\Leftrightarrow\frac{x-1}{2011}+1+\frac{x-2}{2012}+1+\frac{x-3}{2013}+1+\frac{x-4}{2014}+1-\left(x+2010\right)=0\)
\(\Leftrightarrow\frac{x+2010}{2011}+\frac{x+2010}{2012}+\frac{x+2010}{2013}+\frac{x+2010}{2014}-\left(x+2010\right)=0\)
\(\Leftrightarrow\left(x+2010\right)\left(\frac{1}{2011}+\frac{1}{2012}+\frac{1}{2013}+\frac{1}{2014}-1\right)=0\)
\(\Leftrightarrow x=-2010\)
\(\frac{x-1}{2011}+\frac{x-2}{2012}+\frac{x-3}{2013}+\frac{x-4}{2014}=x+2006\)
\(\Leftrightarrow\frac{x+2010}{2011}+\frac{x+2010}{2012}+\frac{x+2010}{2013}+\frac{x+2010}{2014}=x+2010\)
\(\Leftrightarrow\left(x+2010\right)\left(\frac{1}{2011}+\frac{1}{2012}+\frac{1}{2013}+\frac{1}{2014}\right)=x+2010\)
\(\Leftrightarrow\frac{1}{2011}+\frac{1}{2012}+\frac{1}{2013}+\frac{1}{2014}=1\left(\text{Vô lí}\right)\)
\(\text{Vậy phương trình vô nghiệm.}\)
Bài 1: Tính một cách hợp lí:
a) 1234.2014 + 2014. 8766
b) 1357. 2468 -2468.357
c) (14678:2 + 2476). (2576-2575)
d) (195-13.15) : (1945 + 1014)
bài 2: Tìm x
a) 456+ (x - 357) = 1362
b) ( 2345 - x) - 183= 2014
c) (x-2 005). 2006=0
d) 480+45.4= (x+125):5+260
e) 2005. (x-2006)= 2005
g) [(x+50).50-50]:50= 50
1. a. 1234.2014+2014.8766
= 2014.(1234+8766)
= 2014.10000
= 20140000
b. 1357.2468-2468.357
= 2468.(1357-357)
= 2468.1000
= 2468000
c. (14678:2+2476).(2576-2575)-> (nếu hợp lí thì chỗ này phải là 2576)
= (7339+2476).1
= 9815.1
= 9815
d. (195-13.15) : (1945+1014)
= (195-195) : (1945+1014)
= 0 : (1945+1014)
= 0
2. a. 456+(x-357)=1362
=> x-357=1362-456
=> x-357=906
=> x=906+357
=> x=1263
b. (2345-x)-183=2014
=> 2345-x=2014+183
=> 2345-x=2197
=> x=2345-2197
=> x=148
c. (x-2005).2006=0
=> x-2005=0:2006
=> x-2005=0
=> x=2005+0
=> x=2005
d. 480+45.4=(x+125):5+260
=> 480+180=(x+125):5+260
=> 660=(x+125):5+260
=> (x+125):5=660-260
=> (x+125):5=400
=> x+125=400.5
=> x+125=2000
=> x=2000-125
=> x=1875
e. 2005.(x-2006)=2005
=> x-2006=2005:2005
=> x-2006=1
=> x=1+2006
=> x=2007
g. [(x+50).50-50]:50=50
=> (x+50).50-50=50.50
=> (x+50).50-50=2500
=> (x+50).50=2500+50
=> (x+50).50=2550
=> x+50=2550:50
=> x+50=51
=> x=51-50
=> x=1