Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > MPE Home > Th. List > syl5bb | Structured version Visualization version GIF version |
Description: A syllogism inference from two biconditionals. (Contributed by NM, 12-Mar-1993.) |
Ref | Expression |
---|---|
syl5bb.1 | ⊢ (𝜑 ↔ 𝜓) |
syl5bb.2 | ⊢ (𝜒 → (𝜓 ↔ 𝜃)) |
Ref | Expression |
---|---|
syl5bb | ⊢ (𝜒 → (𝜑 ↔ 𝜃)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | syl5bb.1 | . . 3 ⊢ (𝜑 ↔ 𝜓) | |
2 | 1 | a1i 11 | . 2 ⊢ (𝜒 → (𝜑 ↔ 𝜓)) |
3 | syl5bb.2 | . 2 ⊢ (𝜒 → (𝜓 ↔ 𝜃)) | |
4 | 2, 3 | bitrd 278 | 1 ⊢ (𝜒 → (𝜑 ↔ 𝜃)) |
Copyright terms: Public domain | W3C validator |