P Q := match P, Q with | Pconst c, _ => mulC c Q | _, Pconst d => mulC d P | PX P1 v P2, PX Q1 w Q2 => add (mulX v (add (mulX w ( P1 Q1)) ( P1 Q2))) (add (mulX w ( P2 Q1)) ( P2 Q2)) end.
Require Import Import Quoting.