Set Theory :Complements with Ellipses
posted by Ashley on .
Let U= {1,2,3, . . .},
A= {1, 2, 3, . . . ., 39}.
use the roster method to write the set A'
Find A' =
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I understand how complements work. Complement A' is everything outside of set A. However, since U goes on infinitely with its ellipsis, how do I know exactly what the complement of A' is?
Help, please?

simple: A' = {40,41, ...}