求极限lim_{n->无穷} n^2/(2n^2+1) = ( )

求极限：lim(x→无穷)(2^n-7^n)/(2^n+7^n-1)=? 求极限,lim(1+n)(1+n^2)(1+n^4)-----(1+n^2n)=?（n趋于无穷） 求极限 lim(n->无穷)[(3n^2-2)/(3n^2+4)]^[n(n+1)] 求极限 n趋向无穷 2^n+1 + 3^n+1/2^n+3^n (5^n+(-2)^n)/(5^(n+1)+(-2)^(n+1))当n趋近无穷,求极限. 高数求极限 2^n*n!(/n^n) n趋于无穷? 求极限k^2/(n^3+k^3) n趋于无穷,k=1到n 求极限根号(n^2+1)-根号(n^2-2n),n→正无穷 求极限 lim(n无穷)n【(根号（n^2+1)-根号（n^2-1)】 求极限：lim((2n∧2-3n+1)/n+1)×sin n趋于无穷 n趋向正无穷 求极限n*[e^2-(1+1/n)^2n] 求极限:Lim(1+1/n-1/n^2)^n n趋向于正无穷