Can someone explain this to me please?

Question

camerondoherty · Answer

If T = {integers} and subset W = {positive integers}, what is W'?

{1, 2, 3, ...}

{..., -3, -2, -1, 0}

{-3, -2, -1, 0}

{ }

geerky42 · Answer

$T = W\cup W'$

geerky42 · Answer

In other word, W' is subset of T that contains only ALL elements of T that W doesn't have.

geerky42 · Answer

Does that make sense? @camerondoherty

camerondoherty · Answer

Hmmm
Not really...

geerky42 · Answer

Another example: 

Saying $A = \{1, 2, 3, 4, 5\}$

and $B \in A, ~B=\{1\}$.

So $B' = \{2, 3, 4, 5\}$ 

B and B' is both subset of A. 

B have what B' doesn't.

And B' have what B doesn't.

B and B' together have all elements A contains.

Does that help?

geerky42 · Answer

Like, B have any elements from A, then B' takes what's remaining.

camerondoherty · Answer

Yea it does
Thank You!
c:

geerky42 · Answer

Yeah, so do you know what W' is?

camerondoherty · Answer

Well,
Subset W are positive integers...
And Subset W doesnt have negative integers...
So i'd say it was B...

geerky42 · Answer

Right, W doesn't have negative integers and 0, so W' "takes over"