Description: Conjunction idempotence with antecedent. (Contributed by Roy F. Longton, 8-Aug-2005)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | anidmdbi | ⊢ ( ( 𝜑 → ( 𝜓 ∧ 𝜓 ) ) ↔ ( 𝜑 → 𝜓 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | anidm | ⊢ ( ( 𝜓 ∧ 𝜓 ) ↔ 𝜓 ) | |
| 2 | 1 | imbi2i | ⊢ ( ( 𝜑 → ( 𝜓 ∧ 𝜓 ) ) ↔ ( 𝜑 → 𝜓 ) ) |