Theorem nrex 2453

Description: Inference adding restricted existential quantifier to negated wff. (Contributed by NM, 16-Oct-2003.)

Hypothesis

Ref	Expression
nrex.1	⊢ (𝑥 ∈ 𝐴 → ¬ 𝜓)

Assertion

Ref	Expression
nrex	⊢ ¬ ∃𝑥 ∈ 𝐴 𝜓

Proof of Theorem nrex

Step	Hyp	Ref	Expression
1		nrex.1	. . 3 ⊢ (𝑥 ∈ 𝐴 → ¬ 𝜓)
2	1	rgen 2416	. 2 ⊢ ∀𝑥 ∈ 𝐴 ¬ 𝜓
3		ralnex 2358	. 2 ⊢ (∀𝑥 ∈ 𝐴 ¬ 𝜓 ↔ ¬ ∃𝑥 ∈ 𝐴 𝜓)
4	2, 3	mpbi 143	1 ⊢ ¬ ∃𝑥 ∈ 𝐴 𝜓

Syntax hints:  ¬ wn 3   → wi 4   ∈ wcel 1433  ∀wral 2348  ∃wrex 2349

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-in1 576  ax-in2 577  ax-5 1376  ax-gen 1378  ax-ie2 1423

This theorem depends on definitions:  df-bi 115  df-tru 1287  df-fal 1290  df-ral 2353  df-rex 2354

This theorem is referenced by:  rex0  3265  iun0  3734  frec0g  6006  nominpos  8268  sqrt2irr  10541