\(\Leftrightarrow\frac{x-1001}{1006}-1+\frac{x-1003}{1004}-1+\frac{x-1005}{1002}-1+\frac{x-1007}{1000}-1=0\)
\(\Leftrightarrow\frac{x-2007}{1006}+\frac{x-2007}{1004}+\frac{x-2007}{1002}+\frac{x-2007}{1000}=0\)
\(\Leftrightarrow\left(x-2007\right)\left(\frac{1}{1006}+\frac{1}{1004}+\frac{1}{1002}+\frac{1}{1000}\right)=0\)
\(\Leftrightarrow x=2007\)