求证1^2/1.3+2^2/3.5+…+x^2/((2n-1)(2n+1))=(n(n+1)/(2(2n+1)),n属于
求证1^2/1.3+2^2/3.5+…+x^2/((2n-1)(2n+1))=(n(n+1)/(2(2n+1)),n属于
2^n/n*(n+1)
求证1/(n+1)+1/(n+2)+.+1/(3n+1)>1 [n属于N*]
证明不等式:(1/n)^n+(2/n)^n+(3/n)^n+.+(n/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)
证明(1+2/n)^n>5-2/n(n属于N+,n>=3)
求教,N^0+N^1+N^2+N^3.N^n=?公式是什么?(N≠n且N,n都属于自然数)
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+)
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:C(0,n)+2C(1,n)+.+(n+1)C(n,n)=2^n+2^(n-1)