| Metamath Proof Explorer |
< Previous
Next >
Related theorems GIF version |
| Description: Inference commuting conjunction in antecedent. Notational convention: We sometimes suffix with "s" the label of an inference that manipulates an antecedent, leaving the consequent unchanged. The "s" means that the inference eliminates the need for a syllogism (syl 10) -type inference in a proof. |
| Ref | Expression |
|---|---|
| ancoms.1 | ⊢ ((φ ⋀ ψ) → χ) |
| Ref | Expression |
|---|---|
| ancoms | ⊢ ((ψ ⋀ φ) → χ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ancom 435 | . 2 ⊢ ((ψ ⋀ φ) ↔ (φ ⋀ ψ)) | |
| 2 | ancoms.1 | . 2 ⊢ ((φ ⋀ ψ) → χ) | |
| 3 | 1, 2 | sylbi 199 | 1 ⊢ ((ψ ⋀ φ) → χ) |