Section Cosinus2.
Context `{TnEQD:Tarski_neutral_dimensionless_with_decidable_point_equality}.

Lemma lcos2_lg_anga : forall lp l a b, Lcos2 lp l a b -> Lcos2 lp l a b /\ Q_Cong lp /\ Q_Cong l /\ Q_CongA_Acute a /\ Q_CongA_Acute b.