Answer
T' = { x | x is an integer, x$\leq$0}
Work Step by Step
Some of the members of the set U include (but are not limited to) the following: -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12. The members of the set T are as follows: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12. By definition, the members of the set T' are in the set U but not in the set T. Thus, all of the negative numbers are in the set U but not the set T (and thus make the set T').
