Metamath Proof Explorer
Description: The group addition operation is a function. (Contributed by Mario
Carneiro, 14-Aug-2015)
|
|
Ref |
Expression |
|
Hypotheses |
grpplusf.1 |
⊢ 𝐵 = ( Base ‘ 𝐺 ) |
|
|
grpplusf.2 |
⊢ 𝐹 = ( +𝑓 ‘ 𝐺 ) |
|
Assertion |
grpplusf |
⊢ ( 𝐺 ∈ Grp → 𝐹 : ( 𝐵 × 𝐵 ) ⟶ 𝐵 ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
grpplusf.1 |
⊢ 𝐵 = ( Base ‘ 𝐺 ) |
2 |
|
grpplusf.2 |
⊢ 𝐹 = ( +𝑓 ‘ 𝐺 ) |
3 |
|
grpmnd |
⊢ ( 𝐺 ∈ Grp → 𝐺 ∈ Mnd ) |
4 |
1 2
|
mndplusf |
⊢ ( 𝐺 ∈ Mnd → 𝐹 : ( 𝐵 × 𝐵 ) ⟶ 𝐵 ) |
5 |
3 4
|
syl |
⊢ ( 𝐺 ∈ Grp → 𝐹 : ( 𝐵 × 𝐵 ) ⟶ 𝐵 ) |