Theorem funin 5329

Description: The intersection with a function is a function. Exercise 14(a) of [Enderton] p. 53. (Contributed by NM, 19-Mar-2004.) (Proof shortened by Andrew Salmon, 17-Sep-2011.)

Assertion

Ref	Expression
funin	|- ( Fun F -> Fun ( F i^i G ) )

Proof of Theorem funin

Step	Hyp	Ref	Expression
1		inss1 3383	. 2 |- ( F i^i G ) C_ F
2		funss 5277	. 2 |- ( ( F i^i G ) C_ F -> ( Fun F -> Fun ( F i^i G ) ) )
3	1, 2	ax-mp 5	1 |- ( Fun F -> Fun ( F i^i G ) )

Syntax hints:   -> wi 4   i^i cin 3156   C_ wss 3157   Fun wfun 5252

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 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-ext 2178

This theorem depends on definitions:  df-bi 117  df-tru 1367  df-nf 1475  df-sb 1777  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-v 2765  df-in 3163  df-ss 3170  df-br 4034  df-opab 4095  df-rel 4670  df-cnv 4671  df-co 4672  df-fun 5260

This theorem is referenced by: (None)