Theorem tpidm13 3718

Description: Unordered triple { A , B , A } is just an overlong way to write { A , B }. (Contributed by David A. Wheeler, 10-May-2015.)

Assertion

Ref	Expression
tpidm13	|- { A , B , A } = { A , B }

Proof of Theorem tpidm13

Step	Hyp	Ref	Expression
1		tprot 3711	. 2 |- { A , A , B } = { A , B , A }
2		tpidm12 3717	. 2 |- { A , A , B } = { A , B }
3	1, 2	eqtr3i 2216	1 |- { A , B , A } = { A , B }

Syntax hints:   = wceq 1364   {cpr 3619   {ctp 3620

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 710  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-ext 2175

This theorem depends on definitions:  df-bi 117  df-3or 981  df-tru 1367  df-nf 1472  df-sb 1774  df-clab 2180  df-cleq 2186  df-clel 2189  df-nfc 2325  df-v 2762  df-un 3157  df-sn 3624  df-pr 3625  df-tp 3626

This theorem is referenced by: (None)