Description: Absorption into embedded conjunct. (Contributed by NM, 4-Sep-1995) (Proof shortened by Wolf Lammen, 16-Nov-2013)
Ref | Expression | ||
---|---|---|---|
Assertion | anabs1 | ⊢ ( ( ( 𝜑 ∧ 𝜓 ) ∧ 𝜑 ) ↔ ( 𝜑 ∧ 𝜓 ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | simpl | ⊢ ( ( 𝜑 ∧ 𝜓 ) → 𝜑 ) | |
2 | 1 | pm4.71i | ⊢ ( ( 𝜑 ∧ 𝜓 ) ↔ ( ( 𝜑 ∧ 𝜓 ) ∧ 𝜑 ) ) |
3 | 2 | bicomi | ⊢ ( ( ( 𝜑 ∧ 𝜓 ) ∧ 𝜑 ) ↔ ( 𝜑 ∧ 𝜓 ) ) |