Description: Absorption into embedded conjunct. (Contributed by NM, 20-Jul-1996) (Proof shortened by Wolf Lammen, 17-Nov-2013)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | anabs7 | ⊢ ( ( 𝜓 ∧ ( 𝜑 ∧ 𝜓 ) ) ↔ ( 𝜑 ∧ 𝜓 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | simpr | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝜓 ) | |
| 2 | 1 | pm4.71ri | ⊢ ( ( 𝜑 ∧ 𝜓 ) ↔ ( 𝜓 ∧ ( 𝜑 ∧ 𝜓 ) ) ) |
| 3 | 2 | bicomi | ⊢ ( ( 𝜓 ∧ ( 𝜑 ∧ 𝜓 ) ) ↔ ( 𝜑 ∧ 𝜓 ) ) |