Description: The codomain of an arrow is an object. (Contributed by Mario Carneiro, 11-Jan-2017)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | arwrcl.a | ⊢ 𝐴 = ( Arrow ‘ 𝐶 ) | |
| arwdm.b | ⊢ 𝐵 = ( Base ‘ 𝐶 ) | ||
| Assertion | arwcd | ⊢ ( 𝐹 ∈ 𝐴 → ( coda ‘ 𝐹 ) ∈ 𝐵 ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | arwrcl.a | ⊢ 𝐴 = ( Arrow ‘ 𝐶 ) | |
| 2 | arwdm.b | ⊢ 𝐵 = ( Base ‘ 𝐶 ) | |
| 3 | eqid | ⊢ ( Homa ‘ 𝐶 ) = ( Homa ‘ 𝐶 ) | |
| 4 | 1 3 | arwhoma | ⊢ ( 𝐹 ∈ 𝐴 → 𝐹 ∈ ( ( doma ‘ 𝐹 ) ( Homa ‘ 𝐶 ) ( coda ‘ 𝐹 ) ) ) | 
| 5 | 3 2 | homarcl2 | ⊢ ( 𝐹 ∈ ( ( doma ‘ 𝐹 ) ( Homa ‘ 𝐶 ) ( coda ‘ 𝐹 ) ) → ( ( doma ‘ 𝐹 ) ∈ 𝐵 ∧ ( coda ‘ 𝐹 ) ∈ 𝐵 ) ) | 
| 6 | 4 5 | syl | ⊢ ( 𝐹 ∈ 𝐴 → ( ( doma ‘ 𝐹 ) ∈ 𝐵 ∧ ( coda ‘ 𝐹 ) ∈ 𝐵 ) ) | 
| 7 | 6 | simprd | ⊢ ( 𝐹 ∈ 𝐴 → ( coda ‘ 𝐹 ) ∈ 𝐵 ) |