计算：limn→∞3n+13n+1+2n=______．

题型：上海难度：来源：

计算：

lim

n→∞

3n+1

3n+1+2n

=______．

答案

lim

n→∞

3n+1

3n+1+2n

=

lim

n→∞

3n 3n + 1 3n

3n+1 3n + 2n 3n

=

1

3

故答案为：

1

3

．