Do you NEED a backup major when applying for a capped major?

<p>I’m actually an incoming freshman. I’m just planning ahead, not making a definitive schedule, but just thinking under which circumstances I should take what classes. If I don’t need to take math 53 to get applied math as a backup (since I believe that’s the only prereq for applied math not in CS prereqs), I can use that slot to take an elective that I enjoy.</p>