Theorem cotr2 15123

Description: Two ways of saying a relation is transitive. Special instance of cotr2g 15122. (Contributed by RP, 22-Mar-2020.)

Hypotheses

Ref	Expression
cotr2.a	⊢ dom 𝑅 ⊆ 𝐴
cotr2.b	⊢ (dom 𝑅 ∩ ran 𝑅) ⊆ 𝐵
cotr2.c	⊢ ran 𝑅 ⊆ 𝐶

Assertion

Ref	Expression
cotr2	⊢ ((𝑅 ∘ 𝑅) ⊆ 𝑅 ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 ∀𝑧 ∈ 𝐶 ((𝑥𝑅𝑦 ∧ 𝑦𝑅𝑧) → 𝑥𝑅𝑧))

Distinct variable groups:   𝑥,𝑦,𝑧,𝑅   𝑥,𝐴,𝑦,𝑧   𝑦,𝐵,𝑧   𝑧,𝐶

Allowed substitution hints:   𝐵(𝑥)   𝐶(𝑥, 𝑦)

Proof of Theorem cotr2

Step	Hyp	Ref	Expression
1		cotr2.a	. 2 ⊢ dom 𝑅 ⊆ 𝐴
2		incom 4155	. . 3 ⊢ (dom 𝑅 ∩ ran 𝑅) = (ran 𝑅 ∩ dom 𝑅)
3		cotr2.b	. . 3 ⊢ (dom 𝑅 ∩ ran 𝑅) ⊆ 𝐵
4	2, 3	eqsstrri 3978	. 2 ⊢ (ran 𝑅 ∩ dom 𝑅) ⊆ 𝐵
5		cotr2.c	. 2 ⊢ ran 𝑅 ⊆ 𝐶
6	1, 4, 5	cotr2g 15122	1 ⊢ ((𝑅 ∘ 𝑅) ⊆ 𝑅 ↔ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 ∀𝑧 ∈ 𝐶 ((𝑥𝑅𝑦 ∧ 𝑦𝑅𝑧) → 𝑥𝑅𝑧))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401  ∀wral 3077   ∩ cin 3898   ⊆ wss 3899   class class class wbr 5103  dom cdm 5651  ran crn 5652   ∘ ccom 5655

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-12 2213  ax-ext 2733  ax-sep 5249  ax-pr 5391

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-clab 2740  df-cleq 2753  df-clel 2836  df-ral 3078  df-rab 3414  df-v 3453  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-nul 4280  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-br 5104  df-opab 5168  df-xp 5657  df-rel 5658  df-cnv 5659  df-co 5660  df-dm 5661  df-rn 5662

This theorem is used by:  cotr3  15124