Giải phương trình sau:
c. [tex]\frac{2-x}{2005}-1=\frac{1-x}{2006}-\frac{x}{2007}[/tex]
Thanks
[tex]\Leftrightarrow \frac{2-x}{2005}+1=\left ( \frac{1-x}{2006}+1 \right )+\left ( 1-\frac{x}{2007} \right )[/tex]
<=>[TEX]\frac{2007-x}{2005}=\frac{2007-x}{2006}+\frac{2007-x}{2007}[/TEX]
<=>[TEX]\frac{2007-x}{2005}-\frac{2007-x}{2006}-\frac{2007-x}{2007}=0[/TEX]
<=>[TEX](2007-x)(\frac{1}{2005}-\frac{1}{2006}-\frac{1}{2007})=0[/TEX]
<=>2007-x=0 (Vì [TEX]\frac{1}{2005}-\frac{1}{2006}-\frac{1}{2007}<0[/TEX])
<=>x=2007