Bài này đề sai thì phải ??
\(\frac{3-x}{2009}-\frac{2-x}{2010}+\frac{1-x}{2011}=-1\)
\(\Leftrightarrow\frac{3-x}{2009}-\frac{2-x}{2010}+\frac{1-x}{2011}+1=0\)
\(\Leftrightarrow\left(\frac{3-x}{2009}+1\right)-\left(\frac{2-x}{2010}+1\right)+\left(\frac{1-x}{2011}+1\right)=0\)
\(\Leftrightarrow\frac{2012-x}{2009}-\frac{2012-x}{2010}+\frac{2012-x}{2011}=0\)
\(\Leftrightarrow\left(2012-x\right)\left(\frac{1}{2009}-\frac{1}{2010}+\frac{1}{2011}\right)=0\)
Mà \(\frac{1}{2009}-\frac{1}{2010}+\frac{1}{2011}\ne0\)
\(\Leftrightarrow2012-x=0\)
\(\Leftrightarrow x=2012\)
Vậy \(x=2012\)
