Theorem 0qs 36500

Description: Quotient set with the empty set. (Contributed by Peter Mazsa, 14-Sep-2019.)

Assertion

Ref	Expression
0qs	⊢ (∅ / 𝑅) = ∅

Proof of Theorem 0qs

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-qs 8504	. 2 ⊢ (∅ / 𝑅) = {𝑦 ∣ ∃𝑥 ∈ ∅ 𝑦 = [𝑥]𝑅}
2		rex0 4291	. . 3 ⊢ ¬ ∃𝑥 ∈ ∅ 𝑦 = [𝑥]𝑅
3	2	abf 4336	. 2 ⊢ {𝑦 ∣ ∃𝑥 ∈ ∅ 𝑦 = [𝑥]𝑅} = ∅
4	1, 3	eqtri 2766	1 ⊢ (∅ / 𝑅) = ∅

Syntax hints:   = wceq 1539  {cab 2715  ∃wrex 3065  ∅c0 4256  [cec 8496   / cqs 8497

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-ext 2709

This theorem depends on definitions:  df-bi 206  df-an 397  df-tru 1542  df-fal 1552  df-ex 1783  df-sb 2068  df-clab 2716  df-cleq 2730  df-clel 2816  df-ral 3069  df-rex 3070  df-dif 3890  df-nul 4257  df-qs 8504

This theorem is referenced by: (None)