MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  ssrexf Structured version   Visualization version   GIF version

Theorem ssrexf 4010
Description: Restricted existential quantification follows from a subclass relationship. (Contributed by Glauco Siliprandi, 20-Apr-2017.)
Hypotheses
Ref Expression
ssrexf.1 𝑥𝐴
ssrexf.2 𝑥𝐵
Assertion
Ref Expression
ssrexf (𝐴𝐵 → (∃𝑥𝐴 𝜑 → ∃𝑥𝐵 𝜑))

Proof of Theorem ssrexf
StepHypRef Expression
1 ssrexf.1 . . . 4 𝑥𝐴
2 ssrexf.2 . . . 4 𝑥𝐵
31, 2nfss 3939 . . 3 𝑥 𝐴𝐵
4 ssel 3940 . . . 4 (𝐴𝐵 → (𝑥𝐴𝑥𝐵))
54anim1d 612 . . 3 (𝐴𝐵 → ((𝑥𝐴𝜑) → (𝑥𝐵𝜑)))
63, 5eximd 2216 . 2 (𝐴𝐵 → (∃𝑥(𝑥𝐴𝜑) → ∃𝑥(𝑥𝐵𝜑)))
7 df-rex 3131 . 2 (∃𝑥𝐴 𝜑 ↔ ∃𝑥(𝑥𝐴𝜑))
8 df-rex 3131 . 2 (∃𝑥𝐵 𝜑 ↔ ∃𝑥(𝑥𝐵𝜑))
96, 7, 83imtr4g 298 1 (𝐴𝐵 → (∃𝑥𝐴 𝜑 → ∃𝑥𝐵 𝜑))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 398  wex 1780  wcel 2114  wnfc 2957  wrex 3126  wss 3913
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1970  ax-7 2015  ax-8 2116  ax-9 2124  ax-10 2145  ax-11 2161  ax-12 2177  ax-ext 2792
This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-ex 1781  df-nf 1785  df-sb 2070  df-clab 2799  df-cleq 2813  df-clel 2891  df-nfc 2959  df-ral 3130  df-rex 3131  df-v 3475  df-in 3920  df-ss 3930
This theorem is referenced by:  iunxdif3  4993  stoweidlem34  42467
  Copyright terms: Public domain W3C validator