Theorem dfiin3g 4937

Description: Alternate definition of indexed intersection when B is a set. (Contributed by Mario Carneiro, 31-Aug-2015.)

Assertion

Ref	Expression
dfiin3g	|- ( A. x e. A B e. C -> |^|_ x e. A B = |^| ran ( x e. A |-> B ) )

Proof of Theorem dfiin3g

Dummy variable y is distinct from all other variables.

Step	Hyp	Ref	Expression
1		dfiin2g 3960	. 2 |- ( A. x e. A B e. C -> |^|_ x e. A B = |^| { y | E. x e. A y = B } )
2		eqid 2205	. . . 4 |- ( x e. A |-> B ) = ( x e. A |-> B )
3	2	rnmpt 4927	. . 3 |- ran ( x e. A |-> B ) = { y | E. x e. A y = B }
4	3	inteqi 3889	. 2 |- |^| ran ( x e. A |-> B ) = |^| { y | E. x e. A y = B }
5	1, 4	eqtr4di 2256	1 |- ( A. x e. A B e. C -> |^|_ x e. A B = |^| ran ( x e. A |-> B ) )

Syntax hints:   -> wi 4   = wceq 1373   e. wcel 2176   {cab 2191   A.wral 2484   E.wrex 2485   |^|cint 3885   |^|_ciin 3928   |-> cmpt 4106   ran crn 4677

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 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-14 2179  ax-ext 2187  ax-sep 4163  ax-pow 4219  ax-pr 4254

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-nf 1484  df-sb 1786  df-eu 2057  df-mo 2058  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ral 2489  df-rex 2490  df-v 2774  df-un 3170  df-in 3172  df-ss 3179  df-pw 3618  df-sn 3639  df-pr 3640  df-op 3642  df-int 3886  df-iin 3930  df-br 4046  df-opab 4107  df-mpt 4108  df-cnv 4684  df-dm 4686  df-rn 4687

This theorem is referenced by:  dfiin3  4939  riinint  4940