Theorem relfvssunirn 5592

Description: The result of a function value is always a subset of the union of the range, even if it is invalid and thus empty. (Contributed by Stefan O'Rear, 2-Nov-2014.) (Revised by Mario Carneiro, 24-May-2019.)

Assertion

Ref	Expression
relfvssunirn	⊢ (Rel 𝐹 → (𝐹‘𝐴) ⊆ ∪ ran 𝐹)

Proof of Theorem relfvssunirn

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		relelrn 4914	. . . . 5 ⊢ ((Rel 𝐹 ∧ 𝐴𝐹𝑥) → 𝑥 ∈ ran 𝐹)
2	1	ex 115	. . . 4 ⊢ (Rel 𝐹 → (𝐴𝐹𝑥 → 𝑥 ∈ ran 𝐹))
3		elssuni 3878	. . . 4 ⊢ (𝑥 ∈ ran 𝐹 → 𝑥 ⊆ ∪ ran 𝐹)
4	2, 3	syl6 33	. . 3 ⊢ (Rel 𝐹 → (𝐴𝐹𝑥 → 𝑥 ⊆ ∪ ran 𝐹))
5	4	alrimiv 1897	. 2 ⊢ (Rel 𝐹 → ∀𝑥(𝐴𝐹𝑥 → 𝑥 ⊆ ∪ ran 𝐹))
6		fvss 5590	. 2 ⊢ (∀𝑥(𝐴𝐹𝑥 → 𝑥 ⊆ ∪ ran 𝐹) → (𝐹‘𝐴) ⊆ ∪ ran 𝐹)
7	5, 6	syl 14	1 ⊢ (Rel 𝐹 → (𝐹‘𝐴) ⊆ ∪ ran 𝐹)

Syntax hints:   → wi 4  ∀wal 1371   ∈ wcel 2176   ⊆ wss 3166  ∪ cuni 3850   class class class wbr 4044  ran crn 4676  Rel wrel 4680  ‘cfv 5271

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-14 2179  ax-ext 2187  ax-sep 4162  ax-pow 4218  ax-pr 4253

This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-nf 1484  df-sb 1786  df-eu 2057  df-mo 2058  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ral 2489  df-rex 2490  df-v 2774  df-un 3170  df-in 3172  df-ss 3179  df-pw 3618  df-sn 3639  df-pr 3640  df-op 3642  df-uni 3851  df-br 4045  df-opab 4106  df-xp 4681  df-rel 4682  df-cnv 4683  df-dm 4685  df-rn 4686  df-iota 5232  df-fv 5279

This theorem is referenced by:  relrnfvex  5594