求数列{n(n+1)(n+2)}的前n项的和
问题描述:
求数列{n(n+1)(n+2)}的前n项的和
答
S=0.25n(n+1)(n+2)(n+3)能提供方法么?谢谢!是用裂项么?n(n+1)(n+2)=0.25[n(n+1)(n+2)(n+3)-(n-1)n(n+1)(n+2)]
求数列{n(n+1)(n+2)}的前n项的和
S=0.25n(n+1)(n+2)(n+3)能提供方法么?谢谢!是用裂项么?n(n+1)(n+2)=0.25[n(n+1)(n+2)(n+3)-(n-1)n(n+1)(n+2)]