2010²-2009²+2008²-2007².+2²-1²
=(2010²-2009²)+(2008²-2007²)+.+(2²-1²)
=(2010+2009)(2010-2009)+(2008+2007)(2008-2007)+…+(2+1)(2-1)
=(2010+2009)×1+(2008+2007)×1+…+(2+1)×1
=2010+2009+2008+2007+…+2+1
=(1+2010)×2010÷2
=2021055
2010²-2009²+2008²-2007².+2²-1²
=(2010²-2009²)+(2008²-2007²)+.+(2²-1²)
=(2010+2009)(2010-2009)+(2008+2007)(2008-2007)+…+(2+1)(2-1)
=(2010+2009)×1+(2008+2007)×1+…+(2+1)×1
=2010+2009+2008+2007+…+2+1
=(1+2010)×2010÷2
=2021055