Description: Conjoin antecedent to right of consequent. (Contributed by NM, 25-Jul-1999) (Proof shortened by Wolf Lammen, 24-Mar-2013)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | ancrb | ⊢ ( ( 𝜑 → 𝜓 ) ↔ ( 𝜑 → ( 𝜓 ∧ 𝜑 ) ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | iba | ⊢ ( 𝜑 → ( 𝜓 ↔ ( 𝜓 ∧ 𝜑 ) ) ) | |
| 2 | 1 | pm5.74i | ⊢ ( ( 𝜑 → 𝜓 ) ↔ ( 𝜑 → ( 𝜓 ∧ 𝜑 ) ) ) |