Description: Simplification of a conjunction. (Contributed by Jeff Hankins, 28-Jul-2009) (Proof shortened by Wolf Lammen, 6-Apr-2022)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | simplll | ⊢ ( ( ( ( 𝜑 ∧ 𝜓 ) ∧ 𝜒 ) ∧ 𝜃 ) → 𝜑 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | id | ⊢ ( 𝜑 → 𝜑 ) | |
| 2 | 1 | ad3antrrr | ⊢ ( ( ( ( 𝜑 ∧ 𝜓 ) ∧ 𝜒 ) ∧ 𝜃 ) → 𝜑 ) |