Metamath Proof Explorer


Theorem funsssuppss

Description: The support of a function which is a subset of another function is a subset of the support of this other function. (Contributed by AV, 27-Jul-2019)

Ref Expression
Assertion funsssuppss ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) → ( 𝐹 supp 𝑍 ) ⊆ ( 𝐺 supp 𝑍 ) )

Proof

Step Hyp Ref Expression
1 funss ( 𝐹𝐺 → ( Fun 𝐺 → Fun 𝐹 ) )
2 1 impcom ( ( Fun 𝐺𝐹𝐺 ) → Fun 𝐹 )
3 2 funfnd ( ( Fun 𝐺𝐹𝐺 ) → 𝐹 Fn dom 𝐹 )
4 funfn ( Fun 𝐺𝐺 Fn dom 𝐺 )
5 4 birani ( ( Fun 𝐺𝐹𝐺 ) → 𝐺 Fn dom 𝐺 )
6 3 5 jca ( ( Fun 𝐺𝐹𝐺 ) → ( 𝐹 Fn dom 𝐹𝐺 Fn dom 𝐺 ) )
7 6 3adant3 ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) → ( 𝐹 Fn dom 𝐹𝐺 Fn dom 𝐺 ) )
8 7 adantr ( ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) ∧ 𝑍 ∈ V ) → ( 𝐹 Fn dom 𝐹𝐺 Fn dom 𝐺 ) )
9 dmss ( 𝐹𝐺 → dom 𝐹 ⊆ dom 𝐺 )
10 9 3ad2ant2 ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) → dom 𝐹 ⊆ dom 𝐺 )
11 10 adantr ( ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) ∧ 𝑍 ∈ V ) → dom 𝐹 ⊆ dom 𝐺 )
12 dmexg ( 𝐺𝑉 → dom 𝐺 ∈ V )
13 12 3ad2ant3 ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) → dom 𝐺 ∈ V )
14 13 adantr ( ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) ∧ 𝑍 ∈ V ) → dom 𝐺 ∈ V )
15 simpr ( ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) ∧ 𝑍 ∈ V ) → 𝑍 ∈ V )
16 11 14 15 3jca ( ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) ∧ 𝑍 ∈ V ) → ( dom 𝐹 ⊆ dom 𝐺 ∧ dom 𝐺 ∈ V ∧ 𝑍 ∈ V ) )
17 8 16 jca ( ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) ∧ 𝑍 ∈ V ) → ( ( 𝐹 Fn dom 𝐹𝐺 Fn dom 𝐺 ) ∧ ( dom 𝐹 ⊆ dom 𝐺 ∧ dom 𝐺 ∈ V ∧ 𝑍 ∈ V ) ) )
18 funssfv ( ( Fun 𝐺𝐹𝐺𝑥 ∈ dom 𝐹 ) → ( 𝐺𝑥 ) = ( 𝐹𝑥 ) )
19 18 3expa ( ( ( Fun 𝐺𝐹𝐺 ) ∧ 𝑥 ∈ dom 𝐹 ) → ( 𝐺𝑥 ) = ( 𝐹𝑥 ) )
20 eqeq1 ( ( 𝐺𝑥 ) = ( 𝐹𝑥 ) → ( ( 𝐺𝑥 ) = 𝑍 ↔ ( 𝐹𝑥 ) = 𝑍 ) )
21 20 biimpd ( ( 𝐺𝑥 ) = ( 𝐹𝑥 ) → ( ( 𝐺𝑥 ) = 𝑍 → ( 𝐹𝑥 ) = 𝑍 ) )
22 19 21 syl ( ( ( Fun 𝐺𝐹𝐺 ) ∧ 𝑥 ∈ dom 𝐹 ) → ( ( 𝐺𝑥 ) = 𝑍 → ( 𝐹𝑥 ) = 𝑍 ) )
23 22 ralrimiva ( ( Fun 𝐺𝐹𝐺 ) → ∀ 𝑥 ∈ dom 𝐹 ( ( 𝐺𝑥 ) = 𝑍 → ( 𝐹𝑥 ) = 𝑍 ) )
24 23 3adant3 ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) → ∀ 𝑥 ∈ dom 𝐹 ( ( 𝐺𝑥 ) = 𝑍 → ( 𝐹𝑥 ) = 𝑍 ) )
25 24 adantr ( ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) ∧ 𝑍 ∈ V ) → ∀ 𝑥 ∈ dom 𝐹 ( ( 𝐺𝑥 ) = 𝑍 → ( 𝐹𝑥 ) = 𝑍 ) )
26 suppfnss ( ( ( 𝐹 Fn dom 𝐹𝐺 Fn dom 𝐺 ) ∧ ( dom 𝐹 ⊆ dom 𝐺 ∧ dom 𝐺 ∈ V ∧ 𝑍 ∈ V ) ) → ( ∀ 𝑥 ∈ dom 𝐹 ( ( 𝐺𝑥 ) = 𝑍 → ( 𝐹𝑥 ) = 𝑍 ) → ( 𝐹 supp 𝑍 ) ⊆ ( 𝐺 supp 𝑍 ) ) )
27 17 25 26 sylc ( ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) ∧ 𝑍 ∈ V ) → ( 𝐹 supp 𝑍 ) ⊆ ( 𝐺 supp 𝑍 ) )
28 27 expcom ( 𝑍 ∈ V → ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) → ( 𝐹 supp 𝑍 ) ⊆ ( 𝐺 supp 𝑍 ) ) )
29 ssid ∅ ⊆ ∅
30 simpr ( ( 𝐹 ∈ V ∧ 𝑍 ∈ V ) → 𝑍 ∈ V )
31 supp0prc ( ¬ ( 𝐹 ∈ V ∧ 𝑍 ∈ V ) → ( 𝐹 supp 𝑍 ) = ∅ )
32 30 31 nsyl5 ( ¬ 𝑍 ∈ V → ( 𝐹 supp 𝑍 ) = ∅ )
33 simpr ( ( 𝐺 ∈ V ∧ 𝑍 ∈ V ) → 𝑍 ∈ V )
34 supp0prc ( ¬ ( 𝐺 ∈ V ∧ 𝑍 ∈ V ) → ( 𝐺 supp 𝑍 ) = ∅ )
35 33 34 nsyl5 ( ¬ 𝑍 ∈ V → ( 𝐺 supp 𝑍 ) = ∅ )
36 32 35 sseq12d ( ¬ 𝑍 ∈ V → ( ( 𝐹 supp 𝑍 ) ⊆ ( 𝐺 supp 𝑍 ) ↔ ∅ ⊆ ∅ ) )
37 29 36 mpbiri ( ¬ 𝑍 ∈ V → ( 𝐹 supp 𝑍 ) ⊆ ( 𝐺 supp 𝑍 ) )
38 37 a1d ( ¬ 𝑍 ∈ V → ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) → ( 𝐹 supp 𝑍 ) ⊆ ( 𝐺 supp 𝑍 ) ) )
39 28 38 pm2.61i ( ( Fun 𝐺𝐹𝐺𝐺𝑉 ) → ( 𝐹 supp 𝑍 ) ⊆ ( 𝐺 supp 𝑍 ) )