fact: Fixpoint beq_poly pl pr := match pl with | Cst cl => match pr with | Cst cr => decide (cl = cr) | Poly _ _ _ => false end | Poly pl il ql => match pr with | Cst _ => false | Poly pr ir qr => decide (il = ir) && beq_poly pl pr && beq_poly ql qr end end.
imports: Bool PArith DecidableClass Ring Lia