Random but no repeated

I have 10 images I want to load randomly into 3 separate movieclips just once (as to perpetually rotating). I want to be sure that during the random shuffling and placement, that an image is not repeated.

For exampe, I would like the following sampling set of numbers to come up:
1,2,3
1,5,9

I don’t want the following to happen:
2,2,5
7,7,7

How do I avoid having numbers repeated when using ‘random’? Any tips or pointers for tutorials? Thanks.