Theorem simp21 971

Description: Simplification of doubly triple conjunction. (Contributed by NM, 17-Nov-2011.)

Assertion

Ref	Expression
simp21	⊢ ((𝜑 ∧ (𝜓 ∧ 𝜒 ∧ 𝜃) ∧ 𝜏) → 𝜓)

Proof of Theorem simp21

Step	Hyp	Ref	Expression
1		simp1 938	. 2 ⊢ ((𝜓 ∧ 𝜒 ∧ 𝜃) → 𝜓)
2	1	3ad2ant2 960	1 ⊢ ((𝜑 ∧ (𝜓 ∧ 𝜒 ∧ 𝜃) ∧ 𝜏) → 𝜓)

Syntax hints:   → wi 4   ∧ w3a 919

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106

This theorem depends on definitions:  df-bi 115  df-3an 921

This theorem is referenced by:  simpl21  1016  simpr21  1025  simp121  1070  simp221  1079  simp321  1088