1×2×3/2+2×3×4/2+3×4×5/2+……+28×29×30/2

来源：学生作业帮助网编辑：作业帮时间：2024/11/17 08:19:50

1×2×3/2+2×3×4/2+3×4×5/2+……+28×29×30/2
1×2×3/2+2×3×4/2+3×4×5/2+……+28×29×30/2

1×2×3/2+2×3×4/2+3×4×5/2+……+28×29×30/2
9/2

2+2+3+4+1 1+2+3+4×2 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