Description: Given a is equivalent to b, T. is equivalent to b. there exists a proof for a is equivalent to T. (Contributed by Jarvin Udandy, 29-Aug-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | aiffbtbat.1 | ⊢ ( 𝜑 ↔ 𝜓 ) | |
| aiffbtbat.2 | ⊢ ( ⊤ ↔ 𝜓 ) | ||
| Assertion | aiffbtbat | ⊢ ( 𝜑 ↔ ⊤ ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | aiffbtbat.1 | ⊢ ( 𝜑 ↔ 𝜓 ) | |
| 2 | aiffbtbat.2 | ⊢ ( ⊤ ↔ 𝜓 ) | |
| 3 | 1 2 | bitr4i | ⊢ ( 𝜑 ↔ ⊤ ) |