Theorem sseldd 2946

Description: Membership inference from subclass relationship. (Contributed by NM, 14-Dec-2004.)

Hypotheses

Ref	Expression
sseld.1	⊢ (𝜑 → 𝐴 ⊆ 𝐵)
sseldd.2	⊢ (𝜑 → 𝐶 ∈ 𝐴)

Assertion

Ref	Expression
sseldd	⊢ (𝜑 → 𝐶 ∈ 𝐵)

Proof of Theorem sseldd

Step	Hyp	Ref	Expression
1		sseldd.2	. 2 ⊢ (𝜑 → 𝐶 ∈ 𝐴)
2		sseld.1	. . 3 ⊢ (𝜑 → 𝐴 ⊆ 𝐵)
3	2	sseld 2944	. 2 ⊢ (𝜑 → (𝐶 ∈ 𝐴 → 𝐶 ∈ 𝐵))
4	1, 3	mpd 13	1 ⊢ (𝜑 → 𝐶 ∈ 𝐵)

Syntax hints:   → wi 4   ∈ wcel 1393   ⊆ wss 2917

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-11 1397  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022

This theorem depends on definitions:  df-bi 110  df-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-in 2924  df-ss 2931

This theorem is referenced by:  frirrg  4087  ordtri2or2exmid  4296  riotass  5495  eroveu  6197  eroprf  6199  findcard2d  6348  findcard2sd  6349  nnppipi  6441  archnqq  6515  prarloclemlt  6591  fzssp1  8930  elfzoelz  9004  fzofzp1  9083  fzostep1  9093  isermono  9237