(-1)+(+2)+(-3)+(+4)+...+(-99)+(100)

来源：学生作业学帮网编辑：学帮网时间：2024/06/04 12:59:19

(-1)+(+2)+(-3)+(+4)+...+(-99)+(100)
=[(-1)+(+2)]+[(-3)+(+4)]+...+[(-99)+(100)]
=1+1+……+1
=1×(100÷2)
=1×50
=50

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+.