Theorem otelxp1 4647

Description: The first member of an ordered triple of classes in a cross product belongs to first cross product argument. (Contributed by NM, 28-May-2008.)

Assertion

Ref	Expression
otelxp1	|- ( <. <. A , B >. , C >. e. ( ( R X. S ) X. T ) -> A e. R )

Proof of Theorem otelxp1

Step	Hyp	Ref	Expression
1		opelxp1 4645	. 2 |- ( <. <. A , B >. , C >. e. ( ( R X. S ) X. T ) -> <. A , B >. e. ( R X. S ) )
2		opelxp1 4645	. 2 |- ( <. A , B >. e. ( R X. S ) -> A e. R )
3	1, 2	syl 14	1 |- ( <. <. A , B >. , C >. e. ( ( R X. S ) X. T ) -> A e. R )

Syntax hints:   -> wi 4   e. wcel 2141   <.cop 3586   X. cxp 4609

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 704  ax-5 1440  ax-7 1441  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-10 1498  ax-11 1499  ax-i12 1500  ax-bndl 1502  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-i5r 1528  ax-14 2144  ax-ext 2152  ax-sep 4107  ax-pow 4160  ax-pr 4194

This theorem depends on definitions:  df-bi 116  df-3an 975  df-tru 1351  df-nf 1454  df-sb 1756  df-clab 2157  df-cleq 2163  df-clel 2166  df-nfc 2301  df-ral 2453  df-rex 2454  df-v 2732  df-un 3125  df-in 3127  df-ss 3134  df-pw 3568  df-sn 3589  df-pr 3590  df-op 3592  df-opab 4051  df-xp 4617

This theorem is referenced by: (None)