Okay, so basically I'm just showing that two ways to express a regular expression are equal, and to do so, I'm showing they're subsets of each other.
The expression is:
$(A^*B^*)^* \subset (A^*B)^*A^*$
All I have so far is:
Let $x \in (A^*B^*)^*$ so $x$ takes on the form $x = a_1b_1...a_nb_n$ s.t. $n \in \mathbb{N}$ , $a_i \in A^*$ , $b_i \in B^*$
Now I need to find some $x$ in $(A^*B)^*A^*$ such that the $x$'s are the same. However, I can't get anything into a form similar to the one I have above. Any help would be greatly appreciated!