求极限 n趋向无穷 2^n+1 + 3^n+1/2^n+3^n

题目

求极限 n趋向无穷 2^n+1 + 3^n+1/2^n+3^n

答案

2^n+1 + 3^n+1/2^n+3^n 分子分母分别除以3^n,得：
[2×(2/3)^n＋3]/[(2/3)^n＋1],当n趋向于无穷大时,这个值趋向于3.