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authorGravatar Benjamin Barenblat <bbaren@debian.org>2019-02-02 19:29:28 -0500
committerGravatar Benjamin Barenblat <bbaren@debian.org>2019-02-02 19:29:28 -0500
commit1ef7f1c0c6897535a86daa77799714e25638f5e9 (patch)
tree5bcca733632ecc84d2c6b1ee48cb2e557a7adba5 /plugins/micromega/Fourier_util.v
parent3a2fac7bcee36fd9dcb4f39a615c8ac0349abcc9 (diff)
parent9ebf44d84754adc5b64fcf612c6816c02c80462d (diff)
Updated version 8.9.0 from 'upstream/8.9.0'
Diffstat (limited to 'plugins/micromega/Fourier_util.v')
-rw-r--r--plugins/micromega/Fourier_util.v31
1 files changed, 31 insertions, 0 deletions
diff --git a/plugins/micromega/Fourier_util.v b/plugins/micromega/Fourier_util.v
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+Require Export Rbase.
+Require Import Lra.
+
+Open Scope R_scope.
+
+Lemma Rlt_mult_inv_pos : forall x y:R, 0 < x -> 0 < y -> 0 < x * / y.
+intros x y H H0; try assumption.
+replace 0 with (x * 0).
+apply Rmult_lt_compat_l; auto with real.
+ring.
+Qed.
+
+Lemma Rlt_zero_pos_plus1 : forall x:R, 0 < x -> 0 < 1 + x.
+intros x H; try assumption.
+rewrite Rplus_comm.
+apply Rle_lt_0_plus_1.
+red; auto with real.
+Qed.
+
+Lemma Rle_zero_pos_plus1 : forall x:R, 0 <= x -> 0 <= 1 + x.
+ intros; lra.
+Qed.
+
+Lemma Rle_mult_inv_pos : forall x y:R, 0 <= x -> 0 < y -> 0 <= x * / y.
+intros x y H H0; try assumption.
+case H; intros.
+red; left.
+apply Rlt_mult_inv_pos; auto with real.
+rewrite <- H1.
+red; right; ring.
+Qed.