Theorem psubatN 38331

Description: A member of a projective subspace is an atom. (Contributed by NM, 4-Nov-2011.) (New usage is discouraged.)

Hypotheses

Ref	Expression
atpsub.a	⊢ 𝐴 = (Atoms‘𝐾)
atpsub.s	⊢ 𝑆 = (PSubSp‘𝐾)

Assertion

Ref	Expression
psubatN	⊢ ((𝐾 ∈ 𝐵 ∧ 𝑋 ∈ 𝑆 ∧ 𝑌 ∈ 𝑋) → 𝑌 ∈ 𝐴)

Proof of Theorem psubatN

Step	Hyp	Ref	Expression
1		atpsub.a	. . . 4 ⊢ 𝐴 = (Atoms‘𝐾)
2		atpsub.s	. . . 4 ⊢ 𝑆 = (PSubSp‘𝐾)
3	1, 2	psubssat 38330	. . 3 ⊢ ((𝐾 ∈ 𝐵 ∧ 𝑋 ∈ 𝑆) → 𝑋 ⊆ 𝐴)
4	3	sseld 3968	. 2 ⊢ ((𝐾 ∈ 𝐵 ∧ 𝑋 ∈ 𝑆) → (𝑌 ∈ 𝑋 → 𝑌 ∈ 𝐴))
5	4	3impia 1117	1 ⊢ ((𝐾 ∈ 𝐵 ∧ 𝑋 ∈ 𝑆 ∧ 𝑌 ∈ 𝑋) → 𝑌 ∈ 𝐴)

Syntax hints:   → wi 4   ∧ wa 396   ∧ w3a 1087   = wceq 1541   ∈ wcel 2106  ‘cfv 6523  Atomscatm 37838  PSubSpcpsubsp 38072

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-10 2137  ax-11 2154  ax-12 2171  ax-ext 2702  ax-sep 5283  ax-nul 5290  ax-pow 5347  ax-pr 5411

This theorem depends on definitions:  df-bi 206  df-an 397  df-or 846  df-3an 1089  df-tru 1544  df-fal 1554  df-ex 1782  df-nf 1786  df-sb 2068  df-mo 2533  df-eu 2562  df-clab 2709  df-cleq 2723  df-clel 2809  df-nfc 2884  df-ne 2940  df-ral 3061  df-rex 3070  df-rab 3426  df-v 3468  df-dif 3938  df-un 3940  df-in 3942  df-ss 3952  df-nul 4310  df-if 4514  df-pw 4589  df-sn 4614  df-pr 4616  df-op 4620  df-uni 4893  df-br 5133  df-opab 5195  df-mpt 5216  df-id 5558  df-xp 5666  df-rel 5667  df-cnv 5668  df-co 5669  df-dm 5670  df-iota 6475  df-fun 6525  df-fv 6531  df-ov 7387  df-psubsp 38079

This theorem is referenced by: (None)