| Step |
Hyp |
Ref |
Expression |
| 1 |
|
btwncomand.1 |
⊢ ( 𝜑 → 𝑁 ∈ ℕ ) |
| 2 |
|
btwncomand.2 |
⊢ ( 𝜑 → 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ) |
| 3 |
|
btwncomand.3 |
⊢ ( 𝜑 → 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ) |
| 4 |
|
btwncomand.4 |
⊢ ( 𝜑 → 𝐶 ∈ ( 𝔼 ‘ 𝑁 ) ) |
| 5 |
|
btwncomand.5 |
⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝐴 Btwn 〈 𝐵 , 𝐶 〉 ) |
| 6 |
|
btwncom |
⊢ ( ( 𝑁 ∈ ℕ ∧ ( 𝐴 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐵 ∈ ( 𝔼 ‘ 𝑁 ) ∧ 𝐶 ∈ ( 𝔼 ‘ 𝑁 ) ) ) → ( 𝐴 Btwn 〈 𝐵 , 𝐶 〉 ↔ 𝐴 Btwn 〈 𝐶 , 𝐵 〉 ) ) |
| 7 |
1 2 3 4 6
|
syl13anc |
⊢ ( 𝜑 → ( 𝐴 Btwn 〈 𝐵 , 𝐶 〉 ↔ 𝐴 Btwn 〈 𝐶 , 𝐵 〉 ) ) |
| 8 |
7
|
adantr |
⊢ ( ( 𝜑 ∧ 𝜓 ) → ( 𝐴 Btwn 〈 𝐵 , 𝐶 〉 ↔ 𝐴 Btwn 〈 𝐶 , 𝐵 〉 ) ) |
| 9 |
5 8
|
mpbid |
⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝐴 Btwn 〈 𝐶 , 𝐵 〉 ) |