-1-(-2)-(-3)-(-4)-.-(-19)-(-20)怎样解答

来源：学生作业帮助网 编辑：作业帮 时间：2024/11/16 16:33:49
-1-(-2)-(-3)-(-4)-.-(-19)-(-20)怎样解答
x)55 DSWHZ8F-bk$铤^Άt4 F`![#C-C8F 1d;7

-1-(-2)-(-3)-(-4)-.-(-19)-(-20)怎样解答
-1-(-2)-(-3)-(-4)-.-(-19)-(-20)怎样解答

-1-(-2)-(-3)-(-4)-.-(-19)-(-20)怎样解答
(1+2+...+20)-2
=21*10-2
=208

1 2 3 4 1 2 3 4 1 2 3 4 1,2,3,4, 1 2 3 4 1 2 3 4 1,2,3,4, 1,2,3,4, 1,2,3,4, 1,2,3,4, 1 2 3 4 1,2,3,4, 1,2,3,4, 1,2,3,4, 1、2、3、4 1+2+3×4 1,2,3,4 1+2+3+4+.