Formal:
* Sortez les poubelles. (This is the most direct and formal way to say it.)
Informal:
* Sors les poubelles. (This is more casual and appropriate for speaking to family or friends.)
* Vide les poubelles. (This literally translates to "empty the trash cans" but is a common way to say "take out the trash.")
If you are asking someone to take out the trash:
* Peux-tu sortir les poubelles, s'il te plaît? (Can you take out the trash, please?)
* Tu peux vider les poubelles? (Can you empty the trash?)