放缩法证不等式求证：3/2-1/(n+1)＜1+1/(2^2)+1/(3^2)+……+1/n^2＜2-1/n

证明不等式：(1/n)^n+(2/n)^n+(3/n)^n+.+(n/n)^n 证明不等式 1+2n+3n 当n为正偶数,求证n/(n-1)+n(n-2)/(n-1)(n-3)+...+n(n-2).2/(n-1)(n-3).. 证明不等式：(1/n)的n次方+(2/n)的n次方+……+(n/n)的n次方 求证1/(n+1)+1/(n+2)+.+1/(3n+1)>1 [n属于N*] 数列不等式难题!求证：25÷24＜1/n+1 + 1/n+2 + 1/n+3 + .+1/3n+1 ＜11÷10 .. 数学不等式证明题n=1,2,……证明：(1/n)^n+(1/2)^n+……+(n/n)^n第二个是(2/n)^n 求证1×2+2×3+3×4+…+n(n+1)＝13n(n+1)(n+2) (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 设n∈N,n>1.求证：logn (n+1)>log(n+1) (n+2) 不等式求解法：n*(n+1)/2 求证:1+1/2+1/3+...+1/n>In(n+1)+n/2(n+1) (n属于N+)