Metamath Proof Explorer


Theorem cntzcmnss

Description: Any subset in a commutative monoid is a subset of its centralizer. (Contributed by AV, 12-Jan-2019)

Ref Expression
Hypotheses cntzcmnss.b ⊢ 𝐵 = ( Base ‘ 𝐺 )
cntzcmnss.z ⊢ 𝑍 = ( Cntz ‘ 𝐺 )
Assertion cntzcmnss ( ( 𝐺 ∈ CMnd ∧ 𝑆 ⊆ 𝐵 ) → 𝑆 ⊆ ( 𝑍 ‘ 𝑆 ) )

Proof

Step Hyp Ref Expression
1 cntzcmnss.b ⊢ 𝐵 = ( Base ‘ 𝐺 )
2 cntzcmnss.z ⊢ 𝑍 = ( Cntz ‘ 𝐺 )
3 1 2 cntzcmn ⊢ ( ( 𝐺 ∈ CMnd ∧ 𝑆 ⊆ 𝐵 ) → ( 𝑍 ‘ 𝑆 ) = 𝐵 )
4 sseq2 ⊢ ( 𝐵 = ( 𝑍 ‘ 𝑆 ) → ( 𝑆 ⊆ 𝐵 ↔ 𝑆 ⊆ ( 𝑍 ‘ 𝑆 ) ) )
5 4 eqcoms ⊢ ( ( 𝑍 ‘ 𝑆 ) = 𝐵 → ( 𝑆 ⊆ 𝐵 ↔ 𝑆 ⊆ ( 𝑍 ‘ 𝑆 ) ) )
6 5 biimpd ⊢ ( ( 𝑍 ‘ 𝑆 ) = 𝐵 → ( 𝑆 ⊆ 𝐵 → 𝑆 ⊆ ( 𝑍 ‘ 𝑆 ) ) )
7 6 adantld ⊢ ( ( 𝑍 ‘ 𝑆 ) = 𝐵 → ( ( 𝐺 ∈ CMnd ∧ 𝑆 ⊆ 𝐵 ) → 𝑆 ⊆ ( 𝑍 ‘ 𝑆 ) ) )
8 3 7 mpcom ⊢ ( ( 𝐺 ∈ CMnd ∧ 𝑆 ⊆ 𝐵 ) → 𝑆 ⊆ ( 𝑍 ‘ 𝑆 ) )