Proof of Theorem sotr3
Step | Hyp | Ref
| Expression |
1 | | simp3 1136 |
. . . . . . 7
⊢ ((𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴) → 𝑍 ∈ 𝐴) |
2 | | simp2 1135 |
. . . . . . 7
⊢ ((𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴) → 𝑌 ∈ 𝐴) |
3 | 1, 2 | jca 511 |
. . . . . 6
⊢ ((𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴) → (𝑍 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴)) |
4 | | sotric 5522 |
. . . . . 6
⊢ ((𝑅 Or 𝐴 ∧ (𝑍 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴)) → (𝑍𝑅𝑌 ↔ ¬ (𝑍 = 𝑌 ∨ 𝑌𝑅𝑍))) |
5 | 3, 4 | sylan2 592 |
. . . . 5
⊢ ((𝑅 Or 𝐴 ∧ (𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴)) → (𝑍𝑅𝑌 ↔ ¬ (𝑍 = 𝑌 ∨ 𝑌𝑅𝑍))) |
6 | 5 | con2bid 354 |
. . . 4
⊢ ((𝑅 Or 𝐴 ∧ (𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴)) → ((𝑍 = 𝑌 ∨ 𝑌𝑅𝑍) ↔ ¬ 𝑍𝑅𝑌)) |
7 | 6 | adantr 480 |
. . 3
⊢ (((𝑅 Or 𝐴 ∧ (𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴)) ∧ 𝑋𝑅𝑌) → ((𝑍 = 𝑌 ∨ 𝑌𝑅𝑍) ↔ ¬ 𝑍𝑅𝑌)) |
8 | | breq2 5074 |
. . . . . 6
⊢ (𝑍 = 𝑌 → (𝑋𝑅𝑍 ↔ 𝑋𝑅𝑌)) |
9 | 8 | biimprcd 249 |
. . . . 5
⊢ (𝑋𝑅𝑌 → (𝑍 = 𝑌 → 𝑋𝑅𝑍)) |
10 | 9 | adantl 481 |
. . . 4
⊢ (((𝑅 Or 𝐴 ∧ (𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴)) ∧ 𝑋𝑅𝑌) → (𝑍 = 𝑌 → 𝑋𝑅𝑍)) |
11 | | sotr 5518 |
. . . . 5
⊢ ((𝑅 Or 𝐴 ∧ (𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴)) → ((𝑋𝑅𝑌 ∧ 𝑌𝑅𝑍) → 𝑋𝑅𝑍)) |
12 | 11 | expdimp 452 |
. . . 4
⊢ (((𝑅 Or 𝐴 ∧ (𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴)) ∧ 𝑋𝑅𝑌) → (𝑌𝑅𝑍 → 𝑋𝑅𝑍)) |
13 | 10, 12 | jaod 855 |
. . 3
⊢ (((𝑅 Or 𝐴 ∧ (𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴)) ∧ 𝑋𝑅𝑌) → ((𝑍 = 𝑌 ∨ 𝑌𝑅𝑍) → 𝑋𝑅𝑍)) |
14 | 7, 13 | sylbird 259 |
. 2
⊢ (((𝑅 Or 𝐴 ∧ (𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴)) ∧ 𝑋𝑅𝑌) → (¬ 𝑍𝑅𝑌 → 𝑋𝑅𝑍)) |
15 | 14 | expimpd 453 |
1
⊢ ((𝑅 Or 𝐴 ∧ (𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐴 ∧ 𝑍 ∈ 𝐴)) → ((𝑋𝑅𝑌 ∧ ¬ 𝑍𝑅𝑌) → 𝑋𝑅𝑍)) |