令2011=a 则 2009=a-2 2012=a+1
所以 （2011²-2×2011²-2009)
=a²-3a+2
=(a-1)(a-2)
(2011³+2011²-2012)
=a³+a²-a-1
=a²(a+1)-(a+1)
=(a+1)(a²-1)
=(a+1)²(a-1)
所以原式=(a-1)(a-2) 除以(a+1)²(a-1)
=a-2除以(a+1)²
=2009除以2010²