Theorem ssneldd 3182

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 3181	. 2 ⊢ (𝜑 → (¬ 𝐶 ∈ 𝐵 → ¬ 𝐶 ∈ 𝐴))
4	1, 3	mpd 13	1 ⊢ (𝜑 → ¬ 𝐶 ∈ 𝐴)

Syntax hints:  ¬ wn 3   → wi 4   ∈ wcel 2164   ⊆ wss 3153

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 615  ax-in2 616  ax-5 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-11 1517  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-ext 2175

This theorem depends on definitions:  df-bi 117  df-nf 1472  df-sb 1774  df-clab 2180  df-cleq 2186  df-clel 2189  df-in 3159  df-ss 3166

This theorem is referenced by:  0nelrel  4705  addnqprlemfl  7619  addnqprlemfu  7620  mulnqprlemfl  7635  mulnqprlemfu  7636  cauappcvgprlemladdru  7716  fprodntrivap  11727  fprodssdc  11733