Section mCoef.
Load "hCoefStructure".
Load "mCoefStructure".
Let eqA_trans := eqA_trans _ _ _ _ _ _ _ _ _ cs.
Let eqA_sym := eqA_sym _ _ _ _ _ _ _ _ _ cs.
intros a b H H1; apply eqA_trans with (y := a); auto.
Qed.

Theorem plusA_eqA_comp_l :
forall a b c : A, eqA a b -> eqA (plusA a c) (plusA b c).