Theorem dfiin3g 4925

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 3950	. 2 |- ( A. x e. A B e. C -> |^|_ x e. A B = |^| { y | E. x e. A y = B } )
2		eqid 2196	. . . 4 |- ( x e. A |-> B ) = ( x e. A |-> B )
3	2	rnmpt 4915	. . 3 |- ran ( x e. A |-> B ) = { y | E. x e. A y = B }
4	3	inteqi 3879	. 2 |- |^| ran ( x e. A |-> B ) = |^| { y | E. x e. A y = B }
5	1, 4	eqtr4di 2247	1 |- ( A. x e. A B e. C -> |^|_ x e. A B = |^| ran ( x e. A |-> B ) )

Syntax hints:   -> wi 4   = wceq 1364   e. wcel 2167   {cab 2182   A.wral 2475   E.wrex 2476   |^|cint 3875   |^|_ciin 3918   |-> cmpt 4095   ran crn 4665

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-14 2170  ax-ext 2178  ax-sep 4152  ax-pow 4208  ax-pr 4243

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-nf 1475  df-sb 1777  df-eu 2048  df-mo 2049  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-ral 2480  df-rex 2481  df-v 2765  df-un 3161  df-in 3163  df-ss 3170  df-pw 3608  df-sn 3629  df-pr 3630  df-op 3632  df-int 3876  df-iin 3920  df-br 4035  df-opab 4096  df-mpt 4097  df-cnv 4672  df-dm 4674  df-rn 4675

This theorem is referenced by:  dfiin3  4927  riinint  4928