diff --git a/Mathlib/Algebra/Order/Field/Basic.lean b/Mathlib/Algebra/Order/Field/Basic.lean index 18945c2248a16..a3308733a8d7d 100644 --- a/Mathlib/Algebra/Order/Field/Basic.lean +++ b/Mathlib/Algebra/Order/Field/Basic.lean @@ -3,7 +3,7 @@ Copyright (c) 2014 Robert Lewis. All rights reserved. Released under Apache 2.0 license as described in the file LICENSE. Authors: Robert Lewis, Leonardo de Moura, Mario Carneiro, Floris van Doorn ! This file was ported from Lean 3 source module algebra.order.field.basic -! leanprover-community/mathlib commit f835503164c75764d4165d9e630bf27694d73ec6 +! leanprover-community/mathlib commit 5a82b0671532663333e205f422124a98bdfe673f ! Please do not edit these lines, except to modify the commit id ! if you have ported upstream changes. -/ @@ -234,6 +234,13 @@ theorem div_le_of_nonneg_of_le_mul (hb : 0 ≤ b) (hc : 0 ≤ c) (h : a ≤ c * rwa [div_le_iff hb'] #align div_le_of_nonneg_of_le_mul div_le_of_nonneg_of_le_mul +/-- One direction of `div_le_iff` where `c` is allowed to be `0` (but `b` must be nonnegative) -/ +lemma mul_le_of_nonneg_of_le_div (hb : 0 ≤ b) (hc : 0 ≤ c) (h : a ≤ b / c) : a * c ≤ b := by + obtain rfl | hc := hc.eq_or_lt + . simpa using hb + . rwa [le_div_iff hc] at h +#align mul_le_of_nonneg_of_le_div mul_le_of_nonneg_of_le_div + theorem div_le_one_of_le (h : a ≤ b) (hb : 0 ≤ b) : a / b ≤ 1 := div_le_of_nonneg_of_le_mul hb zero_le_one <| by rwa [one_mul] #align div_le_one_of_le div_le_one_of_le