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Mirrors > Home > MPE Home > Th. List > Mathboxes > elinlem | Structured version Visualization version GIF version |
Description: Two ways to say a set is a member of an intersection. (Contributed by RP, 19-Aug-2020.) |
Ref | Expression |
---|---|
elinlem | ⊢ (𝐴 ∈ (𝐵 ∩ 𝐶) ↔ (𝐴 ∈ 𝐵 ∧ ( I ‘𝐴) ∈ 𝐶)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | elin 3980 | . 2 ⊢ (𝐴 ∈ (𝐵 ∩ 𝐶) ↔ (𝐴 ∈ 𝐵 ∧ 𝐴 ∈ 𝐶)) | |
2 | fvi 6989 | . . . . 5 ⊢ (𝐴 ∈ 𝐵 → ( I ‘𝐴) = 𝐴) | |
3 | 2 | eqcomd 2742 | . . . 4 ⊢ (𝐴 ∈ 𝐵 → 𝐴 = ( I ‘𝐴)) |
4 | 3 | eleq1d 2825 | . . 3 ⊢ (𝐴 ∈ 𝐵 → (𝐴 ∈ 𝐶 ↔ ( I ‘𝐴) ∈ 𝐶)) |
5 | 4 | pm5.32i 574 | . 2 ⊢ ((𝐴 ∈ 𝐵 ∧ 𝐴 ∈ 𝐶) ↔ (𝐴 ∈ 𝐵 ∧ ( I ‘𝐴) ∈ 𝐶)) |
6 | 1, 5 | bitri 275 | 1 ⊢ (𝐴 ∈ (𝐵 ∩ 𝐶) ↔ (𝐴 ∈ 𝐵 ∧ ( I ‘𝐴) ∈ 𝐶)) |
Colors of variables: wff setvar class |
Syntax hints: ↔ wb 206 ∧ wa 395 ∈ wcel 2107 ∩ cin 3963 I cid 5583 ‘cfv 6566 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1793 ax-4 1807 ax-5 1909 ax-6 1966 ax-7 2006 ax-8 2109 ax-9 2117 ax-10 2140 ax-12 2176 ax-ext 2707 ax-sep 5303 ax-nul 5313 ax-pr 5439 |
This theorem depends on definitions: df-bi 207 df-an 396 df-or 848 df-3an 1088 df-tru 1541 df-fal 1551 df-ex 1778 df-nf 1782 df-sb 2064 df-mo 2539 df-eu 2568 df-clab 2714 df-cleq 2728 df-clel 2815 df-ral 3061 df-rex 3070 df-rab 3435 df-v 3481 df-dif 3967 df-un 3969 df-in 3971 df-ss 3981 df-nul 4341 df-if 4533 df-sn 4633 df-pr 4635 df-op 4639 df-uni 4914 df-br 5150 df-opab 5212 df-id 5584 df-xp 5696 df-rel 5697 df-cnv 5698 df-co 5699 df-dm 5700 df-iota 6519 df-fun 6568 df-fv 6574 |
This theorem is referenced by: elcnvcnvlem 43603 |
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