1.7求极限lim(x→∞) [(n+1)(n+2)(n+3)]/5 n^3

求极限lim(x→∞)（1/n+2/n+3/n..+n/n） 求极限lim(-2)^n+3^n/(-2)^[n+1]+3^[n+1] (x→∞) 求极限lim [ 2^(n+1)+3^(n+1)]/2^n+3^n (n→∞) lim n →∞ (1^n+3^n+2^n)^1/n,求数列极限 求极限：lim(n→∞)[（3n+1 ）/（3n+2）]^(n+1) 求极限lim(n→∞)(3n^2-n+1)/(2+n^2)? 求极限,lim(x->0) (1-2sinx)^(3/x)lim(n->+∞) (n!-4^n) / (6+ln(n)+ 1.6求极限lim(x→∞) [1+2+3+......+(n-1)]/ n^2 求极限 lim(n→∞)[根号(n^2+4n+5)-(n-1)] = 求极限lim[n→∞](n^2+1)/(2n^2+3) lim((5^n-4^(n-1))/((5^(n+1)+3^(n+2)) n→∞时的极限是多少? lim(n→∞) （n+1）(n+2) (n+3)/5n3次方+n 的极限?