If S = {positive integers} and subset T = {positive integers divisible by 3}, what is T′?

{3, 6, 9, 12, …}

{1, 2, 3, 4, 5, …}

{1, 2, 4, 5, 7, 8, …}

{ }

Question

If S = {positive integers} and subset T = {positive integers divisible by 3}, what is T′? 

 {3, 6, 9, 12, …} 

 {1, 2, 3, 4, 5, …} 

 {1, 2, 4, 5, 7, 8, …} 

 { }

anonymous · Answer

Think of what the set of positive integers looks like (S) and what T looks like.  T' is the complement or what is "left over" once you take all the Ts out of S.

anonymous · Answer

i dont under stand

anonymous · Answer

Ok, start by listing out S.  What do you get?

anonymous · Answer

"S" is the set of positive integers (from the statement of the problem).  Can you list, say the first 10?  It will help you get a handle on the problem, and then I can guide you further, but you have to help me help you.  To list them, you have to first review your class notes on what a positive integer is.  Your teacher most likely told you.