Notation bpow e := (bpow beta e).

Theorem relative_error_round_F2R_emin : (0 < p)%Z -> forall m, let x := F2R (Float beta m emin) in (x <> 0)%R -> (Rabs (round beta fexp rnd x - x) < bpow (-p + 1) * Rabs (round beta fexp rnd x))%R.