Tìm x thuộc Z
a. 4.(x-2)-2.(x+3)=6
b. |x-5|=(-4)2
c. (x+5).(x-9)=0
d. 2011+2010+2009+......+ x=2011
làm hộ mình nhé
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
a: x(x+5)=0
=>\(\left[{}\begin{matrix}x=0\\x+5=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-5\end{matrix}\right.\)
b: 2x(x+3)=0
=>x(x+3)=0
=>\(\left[{}\begin{matrix}x=0\\x+3=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-3\end{matrix}\right.\)
c: \(\left(6-x\right)\left(x+10\right)=0\)
=>\(\left[{}\begin{matrix}6-x=0\\x+10=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=6-0=6\\x=0-10=-10\end{matrix}\right.\)
d: \(\left(5x+20\right)\left(x^2+1\right)=0\)
=>\(5x+20=0\left(x^2+1>=1>0\forall x\right)\)
=>5x=-20
=>x=-4
Ta có:
\(\frac{x+4}{2008}+1+\frac{x+3}{2009}+1=\frac{x+2}{2010}+1+\frac{x+1}{2011}+1\)
\(\frac{x+2012}{2008}+\frac{x+2012}{2009}=\frac{x+2012}{2010}+\frac{x+2012}{2011}\)
\(\left(x+2012\right)\left(\frac{1}{2008}+\frac{1}{2009}-\frac{1}{2010}-\frac{1}{2011}\right)=0\)
\(x=-2012\)
a.|x-1|=3
=>x-1=3 hoặc x-1=-3
=>x=4 hoăc x=-2
vậy...
b.2x+17=15
=>2x=15-17
=>2x=-2
=>x=-1
vậy...
c.tự giải
d.4x-15=-75-x
=>4x+x=-75+15
=>5x=-60
=>x=-12
vậy...
2.2+(-3)+4+...+(-2011)+2012
=(-3+2)+...+(-2011+2010)+2012 (có 2010 cặp)
=-1.2010+2012
=-2010+2012=2
b) x - 17 = ( - 11 ) . ( - 5 )
x -17 = 55
x = 55 + 17
x = 72
Vậy x =...
`Answer:`
\(\left(\frac{x+1}{2013}\right)+\left(\frac{x+2}{2012}\right)+\left(\frac{x+3}{2011}\right)=\left(\frac{x+4}{2010}\right)+\left(\frac{x+5}{2009}\right)+\left(\frac{x+6}{2008}\right)\)
\(\Leftrightarrow\frac{x+1}{2013}+1+\frac{x+2}{2012}+1+\frac{x+3}{2011}+1=\frac{x+4}{2010}+1+\frac{x+5}{2009}+1+\frac{x+6}{2008}+1\)
\(\Leftrightarrow\frac{x+2014}{2013}+\frac{x+2014}{2012}+\frac{x+2014}{2011}=\frac{x+2014}{2010}+\frac{x+2014}{2009}+\frac{x+2014}{2008}\)
\(\Leftrightarrow\frac{x+2014}{2013}+\frac{x+2014}{2012}+\frac{x+2014}{2011}-\frac{x+2014}{2010}-\frac{x+2014}{2009}-\frac{x+2014}{2008}=0\)
\(\Leftrightarrow\left(x+2014\right)\left(\frac{1}{2013}+\frac{1}{2012}+\frac{1}{2011}-\frac{1}{2010}-\frac{1}{2009}-\frac{1}{2008}\right)=0\)
\(\Rightarrow x+2014=0\)
\(\Leftrightarrow x=-2014\)
x+5/2009 + x+4/2010 = x+3/2011 + x+2/2012
=> 1 + x+5/2009 + 1 + x+4/2000 = 1 + x+3/2011 + 1 + x+2/2012
=> x+2014/2009 + x+2014/2000 = x+2004/2011 + x+2014/2012
=> x+2014/2009 + x+2014/2000 - x+2014/2011 - x+2014/2012 = 0
=> (x+2014).(1/2009 + 1/2010 - 1/2011 - 1/2012) = 0
Do 1/2009 > 1/2011; 1/2010 > 1/2012
=> 1/2009 + 1/2010 - 1/2011 - 1/2012 khác 0
=> x + 2014 = 0
=> x = -2014
\(\dfrac{x-1}{2013}+\dfrac{x-2}{2012}+\dfrac{x-3}{2011}=\dfrac{x-4}{2010}+\dfrac{x-5}{2009}+\dfrac{x-6}{2008}\)
\(\Leftrightarrow\dfrac{x-1}{2013}-1+\dfrac{x-2}{2012}-1+\dfrac{x-3}{2011}-1=\dfrac{x-4}{2010}-1+\dfrac{x-5}{2009}-1+\dfrac{x-6}{2008}-1\)
=>x-2014=0
hay x=2014
a.không bít =="
b.|x-5|= -42
|x-5|= 16
=>\(\hept{\begin{cases}x-5=16\\x-5=-16\end{cases}}\)=>\(\hept{\begin{cases}x=16+5\\x=\left(-16\right)+5\end{cases}}\)=>\(\hept{\begin{cases}x=21\\x=\left(-11\right)\end{cases}}\)
Vậy x = 21 hoặc x = (-11)
c.(x+5)(x-9)=0
<=>\(\hept{\begin{cases}x+5=0\\x-9=0\end{cases}}=>\hept{\begin{cases}x=\left(-5\right)\\x=9\end{cases}}\)
Vậy x = (-5) hoặc x = 9
d. theo mk : không có giá trị x thỏa mãn .( đó là ý mk chứ chưa chắc là đúng)
cảm ơn nha