(2²+4²+6²+……+2000²)-(1²+3²+5²+……+1999²)利用因式分解!

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(2²+4²+6²+……+2000²)-(1²+3²+5²+……+1999²)利用因式分解!
(2²+4²+6²+……+2000²)-(1²+3²+5²+……+1999²)
利用因式分解!

(2²+4²+6²+……+2000²)-(1²+3²+5²+……+1999²)利用因式分解!
(2²+4²+6²+……+2000²)-(1²+3²+5²+……+1999²)
=(2²-1²)+(4²-3²)+(6²-5²)+……+(2000²-1999²)
=(2+1)×(2-1)+(4+3)(4-3)+(6+5)(6-5)+···(2000+1999)(2000-1999)
=3+7+11+···3999
=(3+3999)×[(3999-3)÷4+1]÷2
=4002×500
=2001000
注明:[(3999-3)÷4+1]÷2表示有多少个4002

原式=(2²-1²)+(4²-3²)+……+(2000²-1999²)
=(2+1)*(2-1)+(4+3)*(4-3)+……(2000+1999)*(2000-1999)
=1+2+3+4+……+1999+2000
=2001000

=(2² - 1²)+(4² - 3²)+(6² - 5²)+……+(2000² - 1999²)
= (2 + 1)(2 - 1) + (4+3)(4 - 3)+(6+5)(6 - 5)+……+(2000+1999)(2000 - 1999)
=3 + 7 +11 +…… +3999

解:原式=(2000²-1999²)+(1998²-1997²)+……+(2²-1²)
=(2000+1999)(2000-1999)+(1998+1997)(1998-1997)+……+(2+1)(2-1)
=(2000+1999)*1+(1998+1997)*1+……+(2+1)*1
=2000+1999+……+2+1
=(2000+1)*2000/2
=2001000