若lim [3^(n+1)-2a^n]/[3^n+2a^n]=4lim [1-1/3+1/9-…+(-1)^(n-1) ·1/3^(n-1)],则a的取值范围为?A.a3 B.-3

若a>0,则lim{(3^n-a^n)/[3^(n+1)+a^(n+1)]}=? lim 2^n/2^(n+1)+a^n=0 实数a的取值范围?2）若a>0 lim 3^n-a^n / 3^(n+1)+a^(n+1)= lim(n+3)(4-n)/(n-1)(3-2n) lim(n^3+n)/(n^4-3n^2+1) lim[(n+3)/(n+1))]^(n-2) 【n无穷大】 lim(2^n+3^n)^1 (n趋向无穷) 若a≠-2,求(n→∞)lim(2^n-a^n)/[2^n+a^(n+1)] 数列求极限 lim (n->∞) (1/2+3/2^2+...+(2n-1)/2^n)lim (n->∞) n^k/a^nlim (n->∞) a^n/n!lim (n->∞) n次根号下(a) (a>0)lim (n->∞) (log_(a) n)/n lim√2n(√(n+3a)-√n)=1求a 求1.lim(3n-(3n^2+2n)/(n-1)) 2.lim(8+1/(n+1)) 3.lim根号n(根号(n+1)-根号(n-3)) lim n->无穷大(2^n-1)/(3^n+1) lim根号n^2+n+1/3n-2 lim根号n^2+n+1/3n-2=? 求lim n→∞ (1+2/n)^n+3 lim(n→∞)[1-(2n/n+3)] lim(3^2n+5^n)/(1+9^n)=? lim(n→∞)(2n-1/n+3) lim[(4+7+...+3n+1)/(n^2-n)]=