Theorem fixssdm 35900

Description: The fixpoints of a class are a subset of its domain. (Contributed by Scott Fenton, 16-Apr-2012.)

Assertion

Ref	Expression
fixssdm	⊢ Fix 𝐴 ⊆ dom 𝐴

Proof of Theorem fixssdm

Step	Hyp	Ref	Expression
1		df-fix 35853	. 2 ⊢ Fix 𝐴 = dom (𝐴 ∩ I )
2		inss1 4246	. . 3 ⊢ (𝐴 ∩ I ) ⊆ 𝐴
3		dmss 5917	. . 3 ⊢ ((𝐴 ∩ I ) ⊆ 𝐴 → dom (𝐴 ∩ I ) ⊆ dom 𝐴)
4	2, 3	ax-mp 5	. 2 ⊢ dom (𝐴 ∩ I ) ⊆ dom 𝐴
5	1, 4	eqsstri 4031	1 ⊢ Fix 𝐴 ⊆ dom 𝐴

Syntax hints:   ∩ cin 3963   ⊆ wss 3964   I cid 5583  dom cdm 5690   Fix cfix 35829

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1793  ax-4 1807  ax-5 1909  ax-6 1966  ax-7 2006  ax-8 2109  ax-9 2117  ax-ext 2707

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1541  df-fal 1551  df-ex 1778  df-sb 2064  df-clab 2714  df-cleq 2728  df-clel 2815  df-rab 3435  df-v 3481  df-dif 3967  df-un 3969  df-in 3971  df-ss 3981  df-nul 4341  df-if 4533  df-sn 4633  df-pr 4635  df-op 4639  df-br 5150  df-dm 5700  df-fix 35853

This theorem is referenced by: (None)