Notation bpow e := (bpow beta e).Notation format := (generic_format beta (FLT_exp emin prec)).Notation cexp := (canonic_exp beta (FLT_exp emin prec)).

Theorem mult_error_FLX : forall x y, format x -> format y -> format (round beta (FLX_exp prec) rnd (x * y) - (x * y))%R.