n(n+1)(n+2)数列求和k∑ n(n+1)(n+2)=k(k+1)(k+2)(k+3)(k+4)/4n=1求证明

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n(n+1)(n+2)数列求和k∑   n(n+1)(n+2)=k(k+1)(k+2)(k+3)(k+4)/4n=1求证明

n(n+1)(n+2)数列求和k∑ n(n+1)(n+2)=k(k+1)(k+2)(k+3)(k+4)/4n=1求证明
n(n+1)(n+2)数列求和
k
∑ n(n+1)(n+2)=k(k+1)(k+2)(k+3)(k+4)/4
n=1
求证明

n(n+1)(n+2)数列求和k∑ n(n+1)(n+2)=k(k+1)(k+2)(k+3)(k+4)/4n=1求证明
可以用归纳法比较容易
首先,n=1比较容易证明
然后假设n时成立
求n+1时的式子,代入得到

n(n+1)=1/2(n+1)((n+2)-n))

n(n+1)(n+2)=k(k+1)(k+2)(k+3)(k+4)/ 先化简 =2N +N=3n乘n=2k+k 乘3k+9=7k+9 当N=1,3乘1=3,则7k+9=3所以成立 望采纳, Ps. 助人为乐乃人之本性,为大家解题是必要的,有不懂的要追问哦,对本人最大的支持和鼓励是 点赞哦,祝进步!