Proof of Theorem xordidc
Step | Hyp | Ref
| Expression |
1 | | dcbi 938 |
. . . . 5
⊢
(DECID 𝜓 → (DECID 𝜒 → DECID
(𝜓 ↔ 𝜒))) |
2 | 1 | imp 124 |
. . . 4
⊢
((DECID 𝜓 ∧ DECID 𝜒) → DECID (𝜓 ↔ 𝜒)) |
3 | | annimdc 939 |
. . . . . 6
⊢
(DECID 𝜑 → (DECID (𝜓 ↔ 𝜒) → ((𝜑 ∧ ¬ (𝜓 ↔ 𝜒)) ↔ ¬ (𝜑 → (𝜓 ↔ 𝜒))))) |
4 | 3 | imp 124 |
. . . . 5
⊢
((DECID 𝜑 ∧ DECID (𝜓 ↔ 𝜒)) → ((𝜑 ∧ ¬ (𝜓 ↔ 𝜒)) ↔ ¬ (𝜑 → (𝜓 ↔ 𝜒)))) |
5 | | pm5.32 453 |
. . . . . 6
⊢ ((𝜑 → (𝜓 ↔ 𝜒)) ↔ ((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒))) |
6 | 5 | notbii 669 |
. . . . 5
⊢ (¬
(𝜑 → (𝜓 ↔ 𝜒)) ↔ ¬ ((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒))) |
7 | 4, 6 | bitrdi 196 |
. . . 4
⊢
((DECID 𝜑 ∧ DECID (𝜓 ↔ 𝜒)) → ((𝜑 ∧ ¬ (𝜓 ↔ 𝜒)) ↔ ¬ ((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒)))) |
8 | 2, 7 | sylan2 286 |
. . 3
⊢
((DECID 𝜑 ∧ (DECID 𝜓 ∧ DECID 𝜒)) → ((𝜑 ∧ ¬ (𝜓 ↔ 𝜒)) ↔ ¬ ((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒)))) |
9 | | xornbidc 1402 |
. . . . . 6
⊢
(DECID 𝜓 → (DECID 𝜒 → ((𝜓 ⊻ 𝜒) ↔ ¬ (𝜓 ↔ 𝜒)))) |
10 | 9 | imp 124 |
. . . . 5
⊢
((DECID 𝜓 ∧ DECID 𝜒) → ((𝜓 ⊻ 𝜒) ↔ ¬ (𝜓 ↔ 𝜒))) |
11 | 10 | adantl 277 |
. . . 4
⊢
((DECID 𝜑 ∧ (DECID 𝜓 ∧ DECID 𝜒)) → ((𝜓 ⊻ 𝜒) ↔ ¬ (𝜓 ↔ 𝜒))) |
12 | 11 | anbi2d 464 |
. . 3
⊢
((DECID 𝜑 ∧ (DECID 𝜓 ∧ DECID 𝜒)) → ((𝜑 ∧ (𝜓 ⊻ 𝜒)) ↔ (𝜑 ∧ ¬ (𝜓 ↔ 𝜒)))) |
13 | | dcan 935 |
. . . . 5
⊢
((DECID 𝜑 ∧ DECID 𝜓) → DECID (𝜑 ∧ 𝜓)) |
14 | 13 | adantrr 479 |
. . . 4
⊢
((DECID 𝜑 ∧ (DECID 𝜓 ∧ DECID 𝜒)) → DECID (𝜑 ∧ 𝜓)) |
15 | | dcan 935 |
. . . . 5
⊢
((DECID 𝜑 ∧ DECID 𝜒) → DECID (𝜑 ∧ 𝜒)) |
16 | 15 | adantrl 478 |
. . . 4
⊢
((DECID 𝜑 ∧ (DECID 𝜓 ∧ DECID 𝜒)) → DECID (𝜑 ∧ 𝜒)) |
17 | | xornbidc 1402 |
. . . 4
⊢
(DECID (𝜑 ∧ 𝜓) → (DECID (𝜑 ∧ 𝜒) → (((𝜑 ∧ 𝜓) ⊻ (𝜑 ∧ 𝜒)) ↔ ¬ ((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒))))) |
18 | 14, 16, 17 | sylc 62 |
. . 3
⊢
((DECID 𝜑 ∧ (DECID 𝜓 ∧ DECID 𝜒)) → (((𝜑 ∧ 𝜓) ⊻ (𝜑 ∧ 𝜒)) ↔ ¬ ((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒)))) |
19 | 8, 12, 18 | 3bitr4d 220 |
. 2
⊢
((DECID 𝜑 ∧ (DECID 𝜓 ∧ DECID 𝜒)) → ((𝜑 ∧ (𝜓 ⊻ 𝜒)) ↔ ((𝜑 ∧ 𝜓) ⊻ (𝜑 ∧ 𝜒)))) |
20 | 19 | exp32 365 |
1
⊢
(DECID 𝜑 → (DECID 𝜓 → (DECID
𝜒 → ((𝜑 ∧ (𝜓 ⊻ 𝜒)) ↔ ((𝜑 ∧ 𝜓) ⊻ (𝜑 ∧ 𝜒)))))) |