Hey, got a technical question on segments!

I have a 30 day engaged segment and a first time buyer segment.

I want to email those who fit the criteria for both.

Do I have to create a separate segment with that criteria,

Or is there a way to email the profiles that exist in both of these segments, while excluding the profiles that live in just one of the two?

It's kinda pointless to ask since creating a new segment would work just fine... I'm just curious to know.