1-3+5-7+9-11+.-1999=2001计算_数学解答

1-3+5-7+9-11+.-1999=2001计算

人气：341 ℃　时间：2020-03-27 01:18:46

解答

1-3+5-7+9-11+.-1999+2001
=(1-3)+(5-7)+...(1997-1999)+2001
=-2-2...-2(共500个）+2001
=-2*500+2001
=1001