Theorem dfpart2 40007

Description: Alternate definition of the partition predicate. (Contributed by Peter Mazsa, 5-Sep-2021.)

Assertion

Ref	Expression
dfpart2	⊢ (𝑅 Part 𝐴 ↔ ( Disj 𝑅 ∧ (dom 𝑅 / 𝑅) = 𝐴))

Proof of Theorem dfpart2

Step	Hyp	Ref	Expression
1		df-part 40004	. 2 ⊢ (𝑅 Part 𝐴 ↔ ( Disj 𝑅 ∧ 𝑅 DomainQs 𝐴))
2		df-dmqs 39858	. . 3 ⊢ (𝑅 DomainQs 𝐴 ↔ (dom 𝑅 / 𝑅) = 𝐴)
3	2	anbi2i 635	. 2 ⊢ (( Disj 𝑅 ∧ 𝑅 DomainQs 𝐴) ↔ ( Disj 𝑅 ∧ (dom 𝑅 / 𝑅) = 𝐴))
4	1, 3	bitri 278	1 ⊢ (𝑅 Part 𝐴 ↔ ( Disj 𝑅 ∧ (dom 𝑅 / 𝑅) = 𝐴))

This proof depends on syntax axioms:   ↔ wb 209   ∧ wa 401   = wceq 1570  dom cdm 5656   / cqs 8747   DomainQs wdmqs 39342   Disj wdisjALTV 39354   Part wpart 39359

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This proof depends on definitions:  df-bi 210  df-an 402  df-dmqs 39858  df-part 40004

This theorem is used by:  parteq1  40012  parteq2  40013  partim  40046  pet0  40053  petid  40055  petidres  40057  petinidres  40059  petxrnidres  40061  petincnvepres  40098  pet  40100