Theorem ssneldd 3029

Description: If an element is not in a class, it is also not in a subclass of that class. Deduction form. (Contributed by David Moews, 1-May-2017.)

Hypotheses

Ref	Expression
ssneld.1	⊢ (𝜑 → 𝐴 ⊆ 𝐵)
ssneldd.2	⊢ (𝜑 → ¬ 𝐶 ∈ 𝐵)

Assertion

Ref	Expression
ssneldd	⊢ (𝜑 → ¬ 𝐶 ∈ 𝐴)

Proof of Theorem ssneldd

Step	Hyp	Ref	Expression
1		ssneldd.2	. 2 ⊢ (𝜑 → ¬ 𝐶 ∈ 𝐵)
2		ssneld.1	. . 3 ⊢ (𝜑 → 𝐴 ⊆ 𝐵)
3	2	ssneld 3028	. 2 ⊢ (𝜑 → (¬ 𝐶 ∈ 𝐵 → ¬ 𝐶 ∈ 𝐴))
4	1, 3	mpd 13	1 ⊢ (𝜑 → ¬ 𝐶 ∈ 𝐴)

Syntax hints:  ¬ wn 3   → wi 4   ∈ wcel 1439   ⊆ wss 3000

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 580  ax-in2 581  ax-5 1382  ax-7 1383  ax-gen 1384  ax-ie1 1428  ax-ie2 1429  ax-8 1441  ax-11 1443  ax-4 1446  ax-17 1465  ax-i9 1469  ax-ial 1473  ax-i5r 1474  ax-ext 2071

This theorem depends on definitions:  df-bi 116  df-nf 1396  df-sb 1694  df-clab 2076  df-cleq 2082  df-clel 2085  df-in 3006  df-ss 3013

This theorem is referenced by:  0nelrel  4497  addnqprlemfl  7179  addnqprlemfu  7180  mulnqprlemfl  7195  mulnqprlemfu  7196  cauappcvgprlemladdru  7276