Metamath Proof Explorer


Definition df-ghomOLD

Description: Obsolete version of df-ghm as of 15-Mar-2020. Define the set of group homomorphisms from g to h . (Contributed by Paul Chapman, 25-Feb-2008) (New usage is discouraged.)

Ref Expression
Assertion df-ghomOLD GrpOpHom = ( 𝑔 ∈ GrpOp , ∈ GrpOp ↦ { 𝑓 ∣ ( 𝑓 : ran 𝑔 ⟶ ran ∧ ∀ 𝑥 ∈ ran 𝑔𝑦 ∈ ran 𝑔 ( ( 𝑓𝑥 ) ( 𝑓𝑦 ) ) = ( 𝑓 ‘ ( 𝑥 𝑔 𝑦 ) ) ) } )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cghomOLD GrpOpHom
1 vg 𝑔
2 cgr GrpOp
3 vh
4 vf 𝑓
5 4 cv 𝑓
6 1 cv 𝑔
7 6 crn ran 𝑔
8 3 cv
9 8 crn ran
10 7 9 5 wf 𝑓 : ran 𝑔 ⟶ ran
11 vx 𝑥
12 vy 𝑦
13 11 cv 𝑥
14 13 5 cfv ( 𝑓𝑥 )
15 12 cv 𝑦
16 15 5 cfv ( 𝑓𝑦 )
17 14 16 8 co ( ( 𝑓𝑥 ) ( 𝑓𝑦 ) )
18 13 15 6 co ( 𝑥 𝑔 𝑦 )
19 18 5 cfv ( 𝑓 ‘ ( 𝑥 𝑔 𝑦 ) )
20 17 19 wceq ( ( 𝑓𝑥 ) ( 𝑓𝑦 ) ) = ( 𝑓 ‘ ( 𝑥 𝑔 𝑦 ) )
21 20 12 7 wral 𝑦 ∈ ran 𝑔 ( ( 𝑓𝑥 ) ( 𝑓𝑦 ) ) = ( 𝑓 ‘ ( 𝑥 𝑔 𝑦 ) )
22 21 11 7 wral 𝑥 ∈ ran 𝑔𝑦 ∈ ran 𝑔 ( ( 𝑓𝑥 ) ( 𝑓𝑦 ) ) = ( 𝑓 ‘ ( 𝑥 𝑔 𝑦 ) )
23 10 22 wa ( 𝑓 : ran 𝑔 ⟶ ran ∧ ∀ 𝑥 ∈ ran 𝑔𝑦 ∈ ran 𝑔 ( ( 𝑓𝑥 ) ( 𝑓𝑦 ) ) = ( 𝑓 ‘ ( 𝑥 𝑔 𝑦 ) ) )
24 23 4 cab { 𝑓 ∣ ( 𝑓 : ran 𝑔 ⟶ ran ∧ ∀ 𝑥 ∈ ran 𝑔𝑦 ∈ ran 𝑔 ( ( 𝑓𝑥 ) ( 𝑓𝑦 ) ) = ( 𝑓 ‘ ( 𝑥 𝑔 𝑦 ) ) ) }
25 1 3 2 2 24 cmpo ( 𝑔 ∈ GrpOp , ∈ GrpOp ↦ { 𝑓 ∣ ( 𝑓 : ran 𝑔 ⟶ ran ∧ ∀ 𝑥 ∈ ran 𝑔𝑦 ∈ ran 𝑔 ( ( 𝑓𝑥 ) ( 𝑓𝑦 ) ) = ( 𝑓 ‘ ( 𝑥 𝑔 𝑦 ) ) ) } )
26 0 25 wceq GrpOpHom = ( 𝑔 ∈ GrpOp , ∈ GrpOp ↦ { 𝑓 ∣ ( 𝑓 : ran 𝑔 ⟶ ran ∧ ∀ 𝑥 ∈ ran 𝑔𝑦 ∈ ran 𝑔 ( ( 𝑓𝑥 ) ( 𝑓𝑦 ) ) = ( 𝑓 ‘ ( 𝑥 𝑔 𝑦 ) ) ) } )