求证1+1/2^k+1/3^k+...+1/n^k
求证:lim1^k+2^k+3^k+4^k+.n^k/n^(k+1)=1/k+1
请问1^k+2^k+3^k+.+n^k=?
1^k+2^k+3^k+.+n^k 有无表达式
求证:Ck^K+Ck^(k+1)+Ck^(k+2)+Ck^(k+3)+...+Ck^(k+n)=C(k+1)^(k+n+
求证1+1/2^k+1/3^k+...+1/n^k
求证 ∏3^k/(3^k -1)
(1)计算:+2*2!+3*3!+……+n*n!(2)求证:k/(k+1)!=1/k!-1/(k+1)!(3)求证:1/
1^k+2^k+3^k+4^k+5^k.+n^k数列和公式的推导
1k、2k、3k是什么意思
求证:(1)k/(k+1)!=1/k!-1/(k+1)!(2)1/2!+2/3!+…n/(n+1)!=1-1/(n+1)
K-1+K+2+K/3+K*3=2001
3×k×k-2k-1=-1.k等于