Description: An elimination deduction. (Contributed by Alan Sare, 4-Feb-2017) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | eel0T1.1 | ⊢ 𝜑 | |
| eel0T1.2 | ⊢ ( ⊤ → 𝜓 ) | ||
| eel0T1.3 | ⊢ ( 𝜒 → 𝜃 ) | ||
| eel0T1.4 | ⊢ ( ( 𝜑 ∧ 𝜓 ∧ 𝜃 ) → 𝜏 ) | ||
| Assertion | eel0T1 | ⊢ ( 𝜒 → 𝜏 ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | eel0T1.1 | ⊢ 𝜑 | |
| 2 | eel0T1.2 | ⊢ ( ⊤ → 𝜓 ) | |
| 3 | eel0T1.3 | ⊢ ( 𝜒 → 𝜃 ) | |
| 4 | eel0T1.4 | ⊢ ( ( 𝜑 ∧ 𝜓 ∧ 𝜃 ) → 𝜏 ) | |
| 5 | 3anass | ⊢ ( ( 𝜑 ∧ ⊤ ∧ 𝜒 ) ↔ ( 𝜑 ∧ ( ⊤ ∧ 𝜒 ) ) ) | |
| 6 | simpr | ⊢ ( ( 𝜑 ∧ ( ⊤ ∧ 𝜒 ) ) → ( ⊤ ∧ 𝜒 ) ) | |
| 7 | 1 | jctl | ⊢ ( ( ⊤ ∧ 𝜒 ) → ( 𝜑 ∧ ( ⊤ ∧ 𝜒 ) ) ) | 
| 8 | 6 7 | impbii | ⊢ ( ( 𝜑 ∧ ( ⊤ ∧ 𝜒 ) ) ↔ ( ⊤ ∧ 𝜒 ) ) | 
| 9 | truan | ⊢ ( ( ⊤ ∧ 𝜒 ) ↔ 𝜒 ) | |
| 10 | 5 8 9 | 3bitri | ⊢ ( ( 𝜑 ∧ ⊤ ∧ 𝜒 ) ↔ 𝜒 ) | 
| 11 | 2 4 | syl3an2 | ⊢ ( ( 𝜑 ∧ ⊤ ∧ 𝜃 ) → 𝜏 ) | 
| 12 | 3 11 | syl3an3 | ⊢ ( ( 𝜑 ∧ ⊤ ∧ 𝜒 ) → 𝜏 ) | 
| 13 | 10 12 | sylbir | ⊢ ( 𝜒 → 𝜏 ) |