[tex]\frac{x+1}{2009}[/tex]+ [tex]\frac{x+2}{2008}[/tex] +[tex]\frac{x+3}{2007}[/tex] = [tex]\frac{x+10}{2000}[/tex] +[tex]\frac{x+11}{1999}[/tex] +[tex]\frac{x+12}{1998}[/tex]
\frac{x+1}{2009}+\frac{x+2}{2008}+\frac{x+3}{2007}=\frac{x+10}{2000}+\frac{x+11}{1999}+\frac{x+11}{1998}
\Rightarrow \left ( \frac{x+1}{2009}+1 \right )+\left ( \frac{x+2}{2008} +1\right ) +\left ( \frac{x+3}{2007}+1 \right )=\left ( \frac{x+10}{2000}+1 \right )+\left ( \frac{x+11}{1999}+1 \right )+\left ( \frac{x+12}{1998}+1 \right )
[tex]\Rightarrow \frac{x+2010}{2009}+\frac{x+2010}{2008}\frac{x+2010}{2007}=\frac{x+2010}{2000}+\frac{x+2010}{1999}+\frac{x+2010}{1998}
\Rightarrow \frac{x+2010}{2009}+\frac{x+2010}{2008}\frac{x+2010}{2007} -\frac{x+2010}{2000}-\frac{x+2010}{1999}-\frac{x+2010}{1998} = 0
\Rightarrow \left ( x+2010 \right ).\left ( \frac{1}{2009}+\frac{1}{2008}+\frac{1}{2007}-\frac{1}{2000}-\frac{1}{1999}-\frac{1}{1998}\right )
Mà
\left ( \frac{1}{2009}+\frac{1}{2008}+\frac{1}{2007}-\frac{1}{2000}-\frac{1}{1999}-\frac{1}{1998}\right ) \neq 0
Nên
x+2010= 0
\rightarrow x= -2010[/tex]
[TẶNG BẠN] TRỌN BỘ Bí kíp học tốt 08 môn
