# Homework Help: Ordered triples

1. Feb 17, 2010

### amiv4

Moderators note: thread moved to homework area.

Please note, homework assignments or textbook style exercises for which you are seeking assistance are to be posted in the appropriate forum in our https://www.physicsforums.com/forumdisplay.php?f=152" area. This should be done whether the problem is part of one's assigned coursework or just independent study.

Expand the following down to their representations as sets and simplify.
i.) ⟨1, 2, 3⟩1 =
ii.) ⟨1, 2, 2⟩1 =

These are the definitions i have
Recall the deﬁntion of ordered pairs:
⟨a, b⟩ def = {{a}, {a, b}}
Recall the following expansion and simpliﬁcation from class
⟨a, a,⟩ = {{a}, {a, a}} = {{a}, {a}} = {{a}}
Using ordered pairs we could deﬁne ordered triples in two diﬀerent ways:
⟨a, b, c⟩1 def = ⟨a, ⟨b, c⟩⟩
⟨a, b, c⟩2 def = ⟨⟨a, b⟩, c⟩

Last edited by a moderator: Apr 24, 2017
2. Feb 18, 2010

### CompuChip

So... you have the definitions - what's stopping you?
Just plug in the numbers!