Theorem cardsdomelir 9003

Description: A cardinal strictly dominates its members. Equivalent to Proposition 10.37 of [TakeutiZaring] p. 93. This is half of the assertion cardsdomel 9004 and can be proven without the AC. (Contributed by Mario Carneiro, 15-Jan-2013.)

Assertion

Ref	Expression
cardsdomelir	⊢ (𝐴 ∈ (card‘𝐵) → 𝐴 ≺ 𝐵)

Proof of Theorem cardsdomelir

Step	Hyp	Ref	Expression
1		cardon 8974	. . . 4 ⊢ (card‘𝐵) ∈ On
2	1	onelssi 5978	. . . 4 ⊢ (𝐴 ∈ (card‘𝐵) → 𝐴 ⊆ (card‘𝐵))
3		ssdomg 8159	. . . 4 ⊢ ((card‘𝐵) ∈ On → (𝐴 ⊆ (card‘𝐵) → 𝐴 ≼ (card‘𝐵)))
4	1, 2, 3	mpsyl 68	. . 3 ⊢ (𝐴 ∈ (card‘𝐵) → 𝐴 ≼ (card‘𝐵))
5		elfvdm 6363	. . . 4 ⊢ (𝐴 ∈ (card‘𝐵) → 𝐵 ∈ dom card)
6		cardid2 8983	. . . 4 ⊢ (𝐵 ∈ dom card → (card‘𝐵) ≈ 𝐵)
7	5, 6	syl 17	. . 3 ⊢ (𝐴 ∈ (card‘𝐵) → (card‘𝐵) ≈ 𝐵)
8		domentr 8172	. . 3 ⊢ ((𝐴 ≼ (card‘𝐵) ∧ (card‘𝐵) ≈ 𝐵) → 𝐴 ≼ 𝐵)
9	4, 7, 8	syl2anc 573	. 2 ⊢ (𝐴 ∈ (card‘𝐵) → 𝐴 ≼ 𝐵)
10		cardne 8995	. 2 ⊢ (𝐴 ∈ (card‘𝐵) → ¬ 𝐴 ≈ 𝐵)
11		brsdom 8136	. 2 ⊢ (𝐴 ≺ 𝐵 ↔ (𝐴 ≼ 𝐵 ∧ ¬ 𝐴 ≈ 𝐵))
12	9, 10, 11	sylanbrc 572	1 ⊢ (𝐴 ∈ (card‘𝐵) → 𝐴 ≺ 𝐵)

Syntax hints:  ¬ wn 3   → wi 4   ∈ wcel 2145   ⊆ wss 3723   class class class wbr 4787  dom cdm 5250  Oncon0 5865  ‘cfv 6030   ≈ cen 8110   ≼ cdom 8111   ≺ csdm 8112  cardccrd 8965

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1870  ax-4 1885  ax-5 1991  ax-6 2057  ax-7 2093  ax-8 2147  ax-9 2154  ax-10 2174  ax-11 2190  ax-12 2203  ax-13 2408  ax-ext 2751  ax-sep 4916  ax-nul 4924  ax-pow 4975  ax-pr 5035  ax-un 7100

This theorem depends on definitions:  df-bi 197  df-an 383  df-or 837  df-3or 1072  df-3an 1073  df-tru 1634  df-ex 1853  df-nf 1858  df-sb 2050  df-eu 2622  df-mo 2623  df-clab 2758  df-cleq 2764  df-clel 2767  df-nfc 2902  df-ne 2944  df-ral 3066  df-rex 3067  df-rab 3070  df-v 3353  df-sbc 3588  df-dif 3726  df-un 3728  df-in 3730  df-ss 3737  df-pss 3739  df-nul 4064  df-if 4227  df-pw 4300  df-sn 4318  df-pr 4320  df-tp 4322  df-op 4324  df-uni 4576  df-int 4613  df-br 4788  df-opab 4848  df-mpt 4865  df-tr 4888  df-id 5158  df-eprel 5163  df-po 5171  df-so 5172  df-fr 5209  df-we 5211  df-xp 5256  df-rel 5257  df-cnv 5258  df-co 5259  df-dm 5260  df-rn 5261  df-res 5262  df-ima 5263  df-ord 5868  df-on 5869  df-iota 5993  df-fun 6032  df-fn 6033  df-f 6034  df-f1 6035  df-fo 6036  df-f1o 6037  df-fv 6038  df-en 8114  df-dom 8115  df-sdom 8116  df-card 8969

This theorem is referenced by:  cardsdomel  9004  pwsdompw  9232  alephval2  9600  pwcfsdom  9611  tskcard  9809