x=2,y=1
1/xy+1/(x+1)(y+1)+1/(x+2)(y+2)+.+1/(x+2010)(y+2012)
=1/2*1+1/(2+1)(1+1)+1/(2+2)(1+2)+.+1/(2+2010)(1+2012)
=1/2*1+1/3*2+1/4*3+.+1/2012*2013
=1-1/2 +1/2-1/3+1/3-1/4+...+1/2012-1/2013
=1-1/2013
=2012/2013
x=2,y=1 1/xy+1/(x+1)(x+1)+1/(x+2)(y+2)+...
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