Metamath Proof Explorer


Theorem submefmnd

Description: If the base set of a monoid is contained in the base set of the monoid of endofunctions on a set A , contains the identity function and has the function composition as group operation, then its base set is a submonoid of the monoid of endofunctions on set A . Analogous to pgrpsubgsymg . (Contributed by AV, 17-Feb-2024)

Ref Expression
Hypotheses submefmnd.g ⊢ M = EndoFMnd ⁡ A
submefmnd.b ⊢ B = Base M
submefmnd.0 ⊢ 0 ˙ = 0 M
submefmnd.c ⊢ F = Base S
Assertion submefmnd ⊢ A ∈ V → S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → F ∈ SubMnd ⁡ M

Proof

Step Hyp Ref Expression
1 submefmnd.g ⊢ M = EndoFMnd ⁡ A
2 submefmnd.b ⊢ B = Base M
3 submefmnd.0 ⊢ 0 ˙ = 0 M
4 submefmnd.c ⊢ F = Base S
5 1 efmndmnd ⊢ A ∈ V → M ∈ Mnd
6 simpl1 ⊢ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → S ∈ Mnd
7 5 6 anim12i ⊢ A ∈ V ∧ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → M ∈ Mnd ∧ S ∈ Mnd
8 simpl2 ⊢ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → F ⊆ B
9 simpl3 ⊢ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → 0 ˙ ∈ F
10 simpr ⊢ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → + S = f ∈ F , g ∈ F ⟼ f ∘ g
11 resmpo ⊢ F ⊆ B ∧ F ⊆ B → f ∈ B , g ∈ B ⟼ f ∘ g ↾ F × F = f ∈ F , g ∈ F ⟼ f ∘ g
12 11 anidms ⊢ F ⊆ B → f ∈ B , g ∈ B ⟼ f ∘ g ↾ F × F = f ∈ F , g ∈ F ⟼ f ∘ g
13 eqid ⊢ + M = + M
14 1 2 13 efmndplusg ⊢ + M = f ∈ B , g ∈ B ⟼ f ∘ g
15 14 eqcomi ⊢ f ∈ B , g ∈ B ⟼ f ∘ g = + M
16 15 reseq1i ⊢ f ∈ B , g ∈ B ⟼ f ∘ g ↾ F × F = + M ↾ F × F
17 12 16 eqtr3di ⊢ F ⊆ B → f ∈ F , g ∈ F ⟼ f ∘ g = + M ↾ F × F
18 17 3ad2ant2 ⊢ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F → f ∈ F , g ∈ F ⟼ f ∘ g = + M ↾ F × F
19 18 adantr ⊢ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → f ∈ F , g ∈ F ⟼ f ∘ g = + M ↾ F × F
20 10 19 eqtrd ⊢ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → + S = + M ↾ F × F
21 8 9 20 3jca ⊢ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = + M ↾ F × F
22 21 adantl ⊢ A ∈ V ∧ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = + M ↾ F × F
23 2 4 3 mndissubm ⊢ M ∈ Mnd ∧ S ∈ Mnd → F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = + M ↾ F × F → F ∈ SubMnd ⁡ M
24 7 22 23 sylc ⊢ A ∈ V ∧ S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → F ∈ SubMnd ⁡ M
25 24 ex ⊢ A ∈ V → S ∈ Mnd ∧ F ⊆ B ∧ 0 ˙ ∈ F ∧ + S = f ∈ F , g ∈ F ⟼ f ∘ g → F ∈ SubMnd ⁡ M