Description: Add top ad a conjunct. (Contributed by Giovanni Mascellani, 24-May-2019)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | tradd.1 | ⊢ ( 𝜑 ↔ 𝜓 ) | |
| Assertion | tradd | ⊢ ( 𝜑 ↔ ( ⊤ ∧ 𝜓 ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | tradd.1 | ⊢ ( 𝜑 ↔ 𝜓 ) | |
| 2 | truan | ⊢ ( ( ⊤ ∧ 𝜓 ) ↔ 𝜓 ) | |
| 3 | 1 2 | bitr4i | ⊢ ( 𝜑 ↔ ( ⊤ ∧ 𝜓 ) ) |