Theorem fiss 9327

Description: Subset relationship for function fi. (Contributed by Jeff Hankins, 7-Oct-2009.) (Revised by Mario Carneiro, 24-Nov-2013.)

Assertion

Ref	Expression
fiss	⊢ ((𝐵 ∈ 𝑉 ∧ 𝐴 ⊆ 𝐵) → (fi‘𝐴) ⊆ (fi‘𝐵))

Proof of Theorem fiss

Dummy variables 𝑥 𝑦 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		sstr2 3940	. . . . . 6 ⊢ (𝐴 ⊆ 𝐵 → (𝐵 ⊆ 𝑦 → 𝐴 ⊆ 𝑦))
2	1	adantl 481	. . . . 5 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝐴 ⊆ 𝐵) → (𝐵 ⊆ 𝑦 → 𝐴 ⊆ 𝑦))
3	2	anim1d 611	. . . 4 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝐴 ⊆ 𝐵) → ((𝐵 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦) → (𝐴 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)))
4	3	ss2abdv 4017	. . 3 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝐴 ⊆ 𝐵) → {𝑦 ∣ (𝐵 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)} ⊆ {𝑦 ∣ (𝐴 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)})
5		intss 4924	. . 3 ⊢ ({𝑦 ∣ (𝐵 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)} ⊆ {𝑦 ∣ (𝐴 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)} → ∩ {𝑦 ∣ (𝐴 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)} ⊆ ∩ {𝑦 ∣ (𝐵 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)})
6	4, 5	syl 17	. 2 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝐴 ⊆ 𝐵) → ∩ {𝑦 ∣ (𝐴 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)} ⊆ ∩ {𝑦 ∣ (𝐵 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)})
7		ssexg 5268	. . . 4 ⊢ ((𝐴 ⊆ 𝐵 ∧ 𝐵 ∈ 𝑉) → 𝐴 ∈ V)
8	7	ancoms 458	. . 3 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝐴 ⊆ 𝐵) → 𝐴 ∈ V)
9		dffi2 9326	. . 3 ⊢ (𝐴 ∈ V → (fi‘𝐴) = ∩ {𝑦 ∣ (𝐴 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)})
10	8, 9	syl 17	. 2 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝐴 ⊆ 𝐵) → (fi‘𝐴) = ∩ {𝑦 ∣ (𝐴 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)})
11		dffi2 9326	. . 3 ⊢ (𝐵 ∈ 𝑉 → (fi‘𝐵) = ∩ {𝑦 ∣ (𝐵 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)})
12	11	adantr 480	. 2 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝐴 ⊆ 𝐵) → (fi‘𝐵) = ∩ {𝑦 ∣ (𝐵 ⊆ 𝑦 ∧ ∀𝑥 ∈ 𝑦 ∀𝑧 ∈ 𝑦 (𝑥 ∩ 𝑧) ∈ 𝑦)})
13	6, 10, 12	3sstr4d 3989	1 ⊢ ((𝐵 ∈ 𝑉 ∧ 𝐴 ⊆ 𝐵) → (fi‘𝐴) ⊆ (fi‘𝐵))

Syntax hints:   → wi 4   ∧ wa 395   = wceq 1541   ∈ wcel 2113  {cab 2714  ∀wral 3051  Vcvv 3440   ∩ cin 3900   ⊆ wss 3901  ∩ cint 4902  ‘cfv 6492  ficfi 9313

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-3or 1087  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-reu 3351  df-rab 3400  df-v 3442  df-sbc 3741  df-dif 3904  df-un 3906  df-in 3908  df-ss 3918  df-pss 3921  df-nul 4286  df-if 4480  df-pw 4556  df-sn 4581  df-pr 4583  df-op 4587  df-uni 4864  df-int 4903  df-br 5099  df-opab 5161  df-mpt 5180  df-tr 5206  df-id 5519  df-eprel 5524  df-po 5532  df-so 5533  df-fr 5577  df-we 5579  df-xp 5630  df-rel 5631  df-cnv 5632  df-co 5633  df-dm 5634  df-rn 5635  df-res 5636  df-ima 5637  df-ord 6320  df-on 6321  df-lim 6322  df-suc 6323  df-iota 6448  df-fun 6494  df-fn 6495  df-f 6496  df-f1 6497  df-fo 6498  df-f1o 6499  df-fv 6500  df-om 7809  df-1o 8397  df-2o 8398  df-en 8884  df-fin 8887  df-fi 9314

This theorem is referenced by:  fipwuni  9329  elfiun  9333  tgfiss  22935  ordtbas  23136  leordtval2  23156  lecldbas  23163  2ndcsb  23393  ptbasfi  23525  fclscmpi  23973  prdsxmslem2  24473