| Step |
Hyp |
Ref |
Expression |
| 1 |
|
raaan.1 |
⊢ Ⅎ 𝑦 𝜑 |
| 2 |
|
raaan.2 |
⊢ Ⅎ 𝑥 𝜓 |
| 3 |
|
rzal |
⊢ ( 𝐴 = ∅ → ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐴 ( 𝜑 ∧ 𝜓 ) ) |
| 4 |
|
rzal |
⊢ ( 𝐴 = ∅ → ∀ 𝑥 ∈ 𝐴 𝜑 ) |
| 5 |
|
rzal |
⊢ ( 𝐴 = ∅ → ∀ 𝑦 ∈ 𝐴 𝜓 ) |
| 6 |
|
pm5.1 |
⊢ ( ( ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐴 ( 𝜑 ∧ 𝜓 ) ∧ ( ∀ 𝑥 ∈ 𝐴 𝜑 ∧ ∀ 𝑦 ∈ 𝐴 𝜓 ) ) → ( ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐴 ( 𝜑 ∧ 𝜓 ) ↔ ( ∀ 𝑥 ∈ 𝐴 𝜑 ∧ ∀ 𝑦 ∈ 𝐴 𝜓 ) ) ) |
| 7 |
3 4 5 6
|
syl12anc |
⊢ ( 𝐴 = ∅ → ( ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐴 ( 𝜑 ∧ 𝜓 ) ↔ ( ∀ 𝑥 ∈ 𝐴 𝜑 ∧ ∀ 𝑦 ∈ 𝐴 𝜓 ) ) ) |
| 8 |
1
|
r19.28z |
⊢ ( 𝐴 ≠ ∅ → ( ∀ 𝑦 ∈ 𝐴 ( 𝜑 ∧ 𝜓 ) ↔ ( 𝜑 ∧ ∀ 𝑦 ∈ 𝐴 𝜓 ) ) ) |
| 9 |
8
|
ralbidv |
⊢ ( 𝐴 ≠ ∅ → ( ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐴 ( 𝜑 ∧ 𝜓 ) ↔ ∀ 𝑥 ∈ 𝐴 ( 𝜑 ∧ ∀ 𝑦 ∈ 𝐴 𝜓 ) ) ) |
| 10 |
|
nfcv |
⊢ Ⅎ 𝑥 𝐴 |
| 11 |
10 2
|
nfralw |
⊢ Ⅎ 𝑥 ∀ 𝑦 ∈ 𝐴 𝜓 |
| 12 |
11
|
r19.27z |
⊢ ( 𝐴 ≠ ∅ → ( ∀ 𝑥 ∈ 𝐴 ( 𝜑 ∧ ∀ 𝑦 ∈ 𝐴 𝜓 ) ↔ ( ∀ 𝑥 ∈ 𝐴 𝜑 ∧ ∀ 𝑦 ∈ 𝐴 𝜓 ) ) ) |
| 13 |
9 12
|
bitrd |
⊢ ( 𝐴 ≠ ∅ → ( ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐴 ( 𝜑 ∧ 𝜓 ) ↔ ( ∀ 𝑥 ∈ 𝐴 𝜑 ∧ ∀ 𝑦 ∈ 𝐴 𝜓 ) ) ) |
| 14 |
7 13
|
pm2.61ine |
⊢ ( ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐴 ( 𝜑 ∧ 𝜓 ) ↔ ( ∀ 𝑥 ∈ 𝐴 𝜑 ∧ ∀ 𝑦 ∈ 𝐴 𝜓 ) ) |