Metamath Proof Explorer


Theorem rnghmrcl

Description: Reverse closure of a non-unital ring homomorphism. (Contributed by AV, 22-Feb-2020)

Ref Expression
Assertion rnghmrcl ( 𝐹 ∈ ( 𝑅 RngHomo 𝑆 ) → ( 𝑅 ∈ Rng ∧ 𝑆 ∈ Rng ) )

Proof

Step Hyp Ref Expression
1 df-rnghomo RngHomo = ( 𝑟 ∈ Rng , 𝑠 ∈ Rng ↦ ( Base ‘ 𝑟 ) / 𝑣 ( Base ‘ 𝑠 ) / 𝑤 { 𝑓 ∈ ( 𝑤m 𝑣 ) ∣ ∀ 𝑥𝑣𝑦𝑣 ( ( 𝑓 ‘ ( 𝑥 ( +g𝑟 ) 𝑦 ) ) = ( ( 𝑓𝑥 ) ( +g𝑠 ) ( 𝑓𝑦 ) ) ∧ ( 𝑓 ‘ ( 𝑥 ( .r𝑟 ) 𝑦 ) ) = ( ( 𝑓𝑥 ) ( .r𝑠 ) ( 𝑓𝑦 ) ) ) } )
2 1 elmpocl ( 𝐹 ∈ ( 𝑅 RngHomo 𝑆 ) → ( 𝑅 ∈ Rng ∧ 𝑆 ∈ Rng ) )