1减2加3减4加5减6加7加加999减1000加1001的简便运算

2025-06-26 01:29:27
推荐回答(1个)
回答1:

1-2+3-4+5-6+7-8+9-10…+999-1000+1001

=(1-2)+(3-4)+(5-6)+……+(999-1000)+1001
=-1x500+1001
=1001-500
=501