1+(n+2)+(2n+3)+(3n+4)+(4n+5)+……((n-1)n+n)的答案
证明不等式:(1/n)^n+(2/n)^n+(3/n)^n+.+(n/n)^n
如果,n是大于2的整数,计算1/(n-1)(n-2)+1/(n-2)(n-3)+1/(n-3)(n-4)+……+1/(n
用数学归纳法证明:1×2×3+2×3×4+…+n×(n+1)×(n+2)=n(n+1)(n+2)(n+3)4(n∈N
lim(1/n^2+4/n^2+7/n^2+…+3n-1/n^2)
Sn=n(n+2)(n+4)的分项等于1/6[n(n+2)(n+4)(n+5)-(n-1)n(n+2)(n+4)]吗?
(1/(n^2 n 1 ) 2/(n^2 n 2) 3/(n^2 n 3) ……n/(n^2 n n)) 当N越于无穷大
化简:1/(n+1)(n+2)+1/(n+2)(n+3)+1/(n+3)(n+4)
(n+1)(n+2)/1 +(n+2)(n+3)/1 +(n+3)(n+4)/1
(n-1)(n-2)(n-3)(n-4)……(n-m+1)(n-m)n大于m 的计算公式
lim 9^n+4^n+2/5^n-3^2n-1 n趋于无穷大时
证明:1+2C(n,1)+4C(n,2)+...+2^nC(n,n)=3^n .(n∈N+)
n是自然数,0≤n≤101,则| n-1|+|n-2|+|n-3|+…+|n-100|的最小值,