ewrite mulmx_block !(mulmx0, mul0mx, addr0, add0r, repr_mxM).
Qed.

Definition dadd_grepr rG1 rG2 :=Section StandardRepr.

Lemma mx_rsim_socle (sG : socleType rG) (W : sG) (rW : representation) : let modW : mxmodule rG W := component_mx_module rG (socle_base W) in mx_rsim (socle_repr W) rW ->