Could anyone help me? I have to solve this problem, justifying it:

$\{a\_n\}$ and $\{b\_n\}$ are sequences of real numbers. 

Given that: $\displaystyle\lim\_{n\rightarrow\infty} a\_n$ = a > 0 and $\displaystyle\lim\_{n\rightarrow\infty} b\_n$ = $\infty$,

Show that $\displaystyle\lim\_{n\rightarrow\infty} a\_nb\_n = \infty$.