问题 解答题

(2004-1)+(2003-2)+(2002-3)+…+(1003-1002)

答案

(2004-1)+(2003-2)+(2002-3)+…+(1003-1002),

=(2004-1002)+(2003-1001)+(2002-1000)+…+(1003-1),

=1002+1002+1002+…+1002,

=1002×1002,

=1004004.

多项选择题
单项选择题