Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
\(\left|x-2010\right|+\left|x-2011\right|=2012\\ \Rightarrow\left[{}\begin{matrix}2010-x+2011-x=2012\left(x< 2010\right)\\x-2010+2011-x=2012\left(2010\le x< 2011\right)\\x-2010+x-2011=2012\left(x\ge2011\right)\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{2009}{2}\left(tm\right)\\0x=2011\left(vô.lí\right)\\x=\dfrac{6033}{2}\left(tm\right)\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=\dfrac{2009}{2}\\x=\dfrac{6033}{2}\end{matrix}\right.\)
\(\frac{x+4}{2010}+\frac{x+3}{2011}=\frac{x+2}{2012}+\frac{x+1}{2013}\)
\(\Leftrightarrow\left(\frac{x+4}{2010}+1\right)+\left(\frac{x+3}{2011}+1\right)=\left(\frac{x+2}{2012}+1\right)+\left(\frac{x+1}{2013}+1\right)\)
\(\Leftrightarrow\frac{x+2014}{2010}+\frac{x+2014}{2011}=\frac{x+2014}{2012}+\frac{x+2014}{2013}\)
\(\Leftrightarrow\frac{x+2014}{2010}+\frac{x+2014}{2011}-\frac{x+2014}{2012}-\frac{x+2014}{2013}=0\)
\(\Leftrightarrow\left(x+2014\right)\left(\frac{1}{2010}+\frac{1}{2011}-\frac{1}{2012}-\frac{1}{2013}\right)=0\)
\(\Leftrightarrow x+2014=0\)
\(\Leftrightarrow x=-2014\)
V...
|x - 2011| \(\ge\) 2012
\(\Rightarrow\orbr{\begin{cases}x-2011\ge2012\\x-2011\ge-2012\end{cases}\Rightarrow\orbr{\begin{cases}x\ge4023\\x\ge-1\end{cases}}}\)
Vậy x \(\ge\) -1
Ta có
\(\left|x-2011\right|\ge2012\Rightarrow\orbr{\begin{cases}x-2011\ge2012\\x-2011\le2012\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x-2011\ge2012\\2011-x\ge2012\end{cases}\Rightarrow\orbr{\begin{cases}x\ge4023\\-x\ge1\end{cases}}}\orbr{\begin{cases}x\ge4023\\x\le-1\end{cases}}\)
Vậy \(x\ge4023\)hoặc \(x\le-1\)
Lưu ý \(-x>1\Rightarrow x< -1\)
\(\frac{x+4}{2009}+\frac{x+3}{2010}=\frac{x+2}{2011}+\frac{x+1}{2012}\)\(\Leftrightarrow\)\(\left(\frac{x+4}{2009}+1\right)+\left(\frac{x+3}{2010}+1\right)=\left(\frac{x+2}{2011}+1\right)+\left(\frac{x+1}{2012}+1\right)\)
\(=\frac{x+2013}{2009}+\frac{x+2013}{2010}=\frac{x+2013}{2011}+\frac{x+2013}{2012}\)
Biểu thức trên chi thỏa mãn khi x+2013=0
\(\Rightarrow x=-2013\)
mk nghĩ là -2013 vì nếu thay x=-2013 vào thì các phân số sẽ bằng -1.
nếu cộng lại thì đc -2
k nhé
f(x) = x2013 - 2013x2012 + 2013x2011 - 2013x2010 + .... + 2013x - 1
= x2013 - (2012 + 1)x2012 + (2012 + 1)x2011 - (2012 + 1)x2010 + .... + (2012 + 1)x - 1
= x2013 - (x + 1)x2012 + (x + 1)x2011 - (x + 1)x2010 + .... + (x + 1)x - 1
= x2013 - x . x2012 - 1 . x2012 + x . x2011 + 1 . x2011 - x . x2010 - 1 . x2010 + ... + x . x + 1 . x - 1
= x2013 - x2013 - x2012 + x2012 + x2011 - x2011 - x2010 + .... + x2 + x - 1
= x - 1 = 2012 - 1 = 2011
Ta có: x=2011 \(\Rightarrow\)x+1=2012
\(\Rightarrow A=x^{2011}-\left(x+1\right).x^{2010}\)\(+\left(x+1\right)x^{2009}\)\(-\left(x+1\right)x^{2008}+...\)\(-\left(x+1\right)x^2+\left(x+1\right)x-1\)
=\(x^{2011}\)\(-x^{2011}-x^{2010}+x^{2010}+x^{2009}-x^{2009}-\)...\(-x^2+x^2+x-1\)
= \(x-1=2011-1=2010\)
=
a: \(\Leftrightarrow\left\{{}\begin{matrix}x>=2012\\\left(x-2012-x+2011\right)\left(x-2012+x-2011\right)=0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x>=2012\\2x=2023\end{matrix}\right.\Leftrightarrow x\in\varnothing\)
b: Trường hợp 1: x<2010
Pt sẽ là 2010-x+2011-x=2012
=>4021-2x=2012
=>2x=2009
hay x=2009/2(nhận)
TRường hợp 2: 2010<=x<2011
=>x-2010+2011-x=2012
=>1=2012(vô lý)
Trường hợp 3: x>=2011
=>x-2010+x-2011=2012
=>2x=2012+4021=6033
hay x=6033/2(nhận)
