Theorem isfne4b 36535

Description: A condition for a topology to be finer than another. (Contributed by Jeff Hankins, 28-Sep-2009.) (Revised by Mario Carneiro, 11-Sep-2015.)

Hypotheses

Ref	Expression
isfne.1	⊢ 𝑋 = ∪ 𝐴
isfne.2	⊢ 𝑌 = ∪ 𝐵

Assertion

Ref	Expression
isfne4b	⊢ (𝐵 ∈ 𝑉 → (𝐴Fne𝐵 ↔ (𝑋 = 𝑌 ∧ (topGen‘𝐴) ⊆ (topGen‘𝐵))))

Proof of Theorem isfne4b

Step	Hyp	Ref	Expression
1		isfne.1	. . 3 ⊢ 𝑋 = ∪ 𝐴
2		isfne.2	. . 3 ⊢ 𝑌 = ∪ 𝐵
3	1, 2	isfne4 36534	. 2 ⊢ (𝐴Fne𝐵 ↔ (𝑋 = 𝑌 ∧ 𝐴 ⊆ (topGen‘𝐵)))
4		simpr 484	. . . . . . 7 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝑋 = 𝑌) → 𝑋 = 𝑌)
5	4, 1, 2	3eqtr3g 2794	. . . . . 6 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝑋 = 𝑌) → ∪ 𝐴 = ∪ 𝐵)
6		uniexg 7685	. . . . . . 7 ⊢ (𝐵 ∈ 𝑉 → ∪ 𝐵 ∈ V)
7	6	adantr 480	. . . . . 6 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝑋 = 𝑌) → ∪ 𝐵 ∈ V)
8	5, 7	eqeltrd 2836	. . . . 5 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝑋 = 𝑌) → ∪ 𝐴 ∈ V)
9		uniexb 7709	. . . . 5 ⊢ (𝐴 ∈ V ↔ ∪ 𝐴 ∈ V)
10	8, 9	sylibr 234	. . . 4 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝑋 = 𝑌) → 𝐴 ∈ V)
11		simpl 482	. . . 4 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝑋 = 𝑌) → 𝐵 ∈ 𝑉)
12		tgss3 22930	. . . 4 ⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ 𝑉) → ((topGen‘𝐴) ⊆ (topGen‘𝐵) ↔ 𝐴 ⊆ (topGen‘𝐵)))
13	10, 11, 12	syl2anc 584	. . 3 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝑋 = 𝑌) → ((topGen‘𝐴) ⊆ (topGen‘𝐵) ↔ 𝐴 ⊆ (topGen‘𝐵)))
14	13	pm5.32da 579	. 2 ⊢ (𝐵 ∈ 𝑉 → ((𝑋 = 𝑌 ∧ (topGen‘𝐴) ⊆ (topGen‘𝐵)) ↔ (𝑋 = 𝑌 ∧ 𝐴 ⊆ (topGen‘𝐵))))
15	3, 14	bitr4id 290	1 ⊢ (𝐵 ∈ 𝑉 → (𝐴Fne𝐵 ↔ (𝑋 = 𝑌 ∧ (topGen‘𝐴) ⊆ (topGen‘𝐵))))

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   = wceq 1541   ∈ wcel 2113  Vcvv 3440   ⊆ wss 3901  ∪ cuni 4863   class class class wbr 5098  ‘cfv 6492  topGenctg 17357  Fnecfne 36530

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 1968  ax-7 2009  ax-8 2115  ax-9 2123  ax-10 2146  ax-11 2162  ax-12 2184  ax-ext 2708  ax-sep 5241  ax-nul 5251  ax-pow 5310  ax-pr 5377  ax-un 7680

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1544  df-fal 1554  df-ex 1781  df-nf 1785  df-sb 2068  df-mo 2539  df-eu 2569  df-clab 2715  df-cleq 2728  df-clel 2811  df-nfc 2885  df-ne 2933  df-ral 3052  df-rex 3061  df-rab 3400  df-v 3442  df-dif 3904  df-un 3906  df-in 3908  df-ss 3918  df-nul 4286  df-if 4480  df-pw 4556  df-sn 4581  df-pr 4583  df-op 4587  df-uni 4864  df-iun 4948  df-br 5099  df-opab 5161  df-mpt 5180  df-id 5519  df-xp 5630  df-rel 5631  df-cnv 5632  df-co 5633  df-dm 5634  df-iota 6448  df-fun 6494  df-fv 6500  df-topgen 17363  df-fne 36531

This theorem is referenced by:  fnetr  36545  fneval  36546