I understand that, at least in the context of using a major scale, a perfect cadence is V-I. That is, if I were playing a piece in C major, I could play a chord similiar to the G major triad followed by a chord similar to the C major triad.*
What about in a minor key? If my piece is in the key of A minor, would I achieve a perfect cadence by playing an E major chord followed by an A major chord? Or would I instead have to play an E minor chord followed by an A minor chord?
Footnotes:
*I know that some theorists say that its not a perfect cadence unless the highest note of the I chord is the tonic note. For my purposes, however, I'm not using that convention.