1/2+1/4+1/8+1/16+1/32+1/64+1/128+1/256……+1/2^n
2^n/n*(n+1)
证明不等式:(1/n)^n+(2/n)^n+(3/n)^n+.+(n/n)^n
(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
M=(N-1)×1+(N-2)×2+(N-3)×4+(N-4)×8+(N-5)×16+(N-6)×32+(N-7)×64
lim(1/n^2+4/n^2+7/n^2+…+3n-1/n^2)
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
求极限 lim n[1/(n^2+1)+1/(n^2+2^2)+……+1/(n^n+n^n)] (n趋向于无穷大,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
证明不等式:(1/n)的n次方+(2/n)的n次方+……+(n/n)的n次方
证明1/(n+1)+1/(n+2)+1/(n+3)+……+1/(n+n)
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