Theorem ifex 4577

Description: Existence of the conditional operator (inference form). (Contributed by NM, 2-Sep-2004.)

Hypotheses

Ref	Expression
ifex.1	⊢ 𝐴 ∈ V
ifex.2	⊢ 𝐵 ∈ V

Assertion

Ref	Expression
ifex	⊢ if(𝜑, 𝐴, 𝐵) ∈ V

Proof of Theorem ifex

Step	Hyp	Ref	Expression
1		ifex.1	. 2 ⊢ 𝐴 ∈ V
2		ifex.2	. 2 ⊢ 𝐵 ∈ V
3		ifexg 4576	. 2 ⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ V) → if(𝜑, 𝐴, 𝐵) ∈ V)
4	1, 2, 3	mp2an 426	1 ⊢ if(𝜑, 𝐴, 𝐵) ∈ V

Syntax hints:   ∈ wcel 2200  Vcvv 2799  ifcif 3602

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 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-sep 4202  ax-pr 4293  ax-un 4524

This theorem depends on definitions:  df-bi 117  df-tru 1398  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-rex 2514  df-rab 2517  df-v 2801  df-un 3201  df-in 3203  df-ss 3210  df-if 3603  df-pw 3651  df-sn 3672  df-pr 3673  df-uni 3889

This theorem is referenced by:  elply2  15417  pw1map  16390  nnnninfex  16418