Proof of Theorem exbirVD
Step | Hyp | Ref
| Expression |
1 | | idn3 42124 |
. . . . . 6
⊢ ( ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) , (𝜑 ∧ 𝜓) , 𝜃 ▶ 𝜃 ) |
2 | | idn1 42083 |
. . . . . . 7
⊢ ( ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) ▶ ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) ) |
3 | | idn2 42122 |
. . . . . . 7
⊢ ( ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) , (𝜑 ∧ 𝜓) ▶ (𝜑 ∧ 𝜓) ) |
4 | | id 22 |
. . . . . . 7
⊢ (((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) → ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃))) |
5 | 2, 3, 4 | e12 42233 |
. . . . . 6
⊢ ( ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) , (𝜑 ∧ 𝜓) ▶ (𝜒 ↔ 𝜃) ) |
6 | | biimpr 219 |
. . . . . . 7
⊢ ((𝜒 ↔ 𝜃) → (𝜃 → 𝜒)) |
7 | 6 | com12 32 |
. . . . . 6
⊢ (𝜃 → ((𝜒 ↔ 𝜃) → 𝜒)) |
8 | 1, 5, 7 | e32 42267 |
. . . . 5
⊢ ( ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) , (𝜑 ∧ 𝜓) , 𝜃 ▶ 𝜒 ) |
9 | 8 | in3 42118 |
. . . 4
⊢ ( ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) , (𝜑 ∧ 𝜓) ▶ (𝜃 → 𝜒) ) |
10 | 9 | in2 42114 |
. . 3
⊢ ( ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) ▶ ((𝜑 ∧ 𝜓) → (𝜃 → 𝜒)) ) |
11 | | pm3.3 448 |
. . 3
⊢ (((𝜑 ∧ 𝜓) → (𝜃 → 𝜒)) → (𝜑 → (𝜓 → (𝜃 → 𝜒)))) |
12 | 10, 11 | e1a 42136 |
. 2
⊢ ( ((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) ▶ (𝜑 → (𝜓 → (𝜃 → 𝜒))) ) |
13 | 12 | in1 42080 |
1
⊢ (((𝜑 ∧ 𝜓) → (𝜒 ↔ 𝜃)) → (𝜑 → (𝜓 → (𝜃 → 𝜒)))) |