求证:1+1/2+1/3+1/4+1/8+1/6+1/7+^+1/(2n-1)>n/2
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)..
求证1/(n+1)+1/(n+2)+.+1/(3n+1)>1 [n属于N*]
设n∈N,n>1.求证:logn (n+1)>log(n+1) (n+2)
求证:1+1/2+1/3+...+1/n>In(n+1)+n/2(n+1) (n属于N+)
数学定理证明求证2^n-1=2^n-1+2^n-2+2^n-3+.+2^n-n
设n属于N,n>1,求证logn (n+1)>logn+1 (n+2)
已知 n>1且n属于N* ,求证logn(n+1)>logn+1(n+2)
求证c(n,1)+2c(n,2)+3c(n,3)+...+nc(n,n)=n2^(n-1)
证明不等式:(1/n)^n+(2/n)^n+(3/n)^n+.+(n/n)^n
求证1×2+2×3+3×4+…+n(n+1)=13n(n+1)(n+2)
求证:C(0,n)+2C(1,n)+.+(n+1)C(n,n)=2^n+2^(n-1)
求证1+1/2+1/3+...+1/n>In(n+1) (n属于N+)