x-1/2013 + x-2/2012 + x-3/2011 + x-4/2010 = x-5/2009 + x-6/2008

`(x - 1)/2013 + (x - 2)/2012 + (x - 3)/2011 + (x - 4)/2010 = (x - 5)/2009 + (x - 6)/2008`

`<=> ((x - 1)/2013 - 1) + ((x - 2)/2012 - 1) + ((x - 3)/2011 - 1) + ((x - 4)/2010 - 1) = ((x - 5)/2009 - 1) + ((x - 6)/2008 - 1)`

`<=> (2014 - x)/2013 + (2014 - x)/2012 + (2014 - x)/2011 + (2014 - x)/2010 = (2014 - x)/2009 - (2014 - x)/2009`

`<=> (2014 - x)/2013 + (2014 - x)/2012 + (2014 - x)/2011 + (2014 - x)/2010 - (2014 - x)/2009 - (2014 - x)/2009 = 0`

`<=> (2014 - x)(1/2013 + 1/2012 + 1/2011 + 1/2010 - 1/2009 - 1/2008) = 0`

`<=> 2014 - x = 0 : 1/2013 + 1/2012 + 1/2011 + 1/2010 - 1/2009 - 1/2008`

`<=> 2014 - x = 0`

`<=> x = 2014 - 0`

`<=> x = 2014`

`text{Vậy: phương trình có tập nghiệm là:}` `S = {2014}`