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authorGravatar desmettr <desmettr@85f007b7-540e-0410-9357-904b9bb8a0f7>2001-12-05 12:33:41 +0000
committerGravatar desmettr <desmettr@85f007b7-540e-0410-9357-904b9bb8a0f7>2001-12-05 12:33:41 +0000
commite52b55b2e60a38f61b0fd6b161e081e825bcf8be (patch)
tree0b6f49c85b8e76add1a331c4c3d15dd1305ba52d /theories
parent3f054c565ffed6356e3eaea15495eebf637ef126 (diff)
*** empty log message ***
git-svn-id: svn+ssh://scm.gforge.inria.fr/svn/coq/trunk@2269 85f007b7-540e-0410-9357-904b9bb8a0f7
Diffstat (limited to 'theories')
-rw-r--r--theories/Reals/Rtrigo.v8
1 files changed, 6 insertions, 2 deletions
diff --git a/theories/Reals/Rtrigo.v b/theories/Reals/Rtrigo.v
index fa07efe98..bc7892207 100644
--- a/theories/Reals/Rtrigo.v
+++ b/theories/Reals/Rtrigo.v
@@ -24,8 +24,6 @@ Save.
Parameter sin : R->R.
Parameter cos : R->R.
-Axiom sin2_cos2 : (x:R) ``(Rsqr (sin x)) + (Rsqr (cos x))==1``.
-
Axiom sin_plus : (x,y:R) ``(sin (x+y))==(sin x)*(cos y)+(cos x)*(sin y)``.
Axiom sin_minus : (x,y:R) ``(sin (x-y))==(sin x)*(cos y)-(cos x)*(sin y)``.
@@ -39,6 +37,12 @@ Axiom cos_0 : ``(cos 0)==1``.
Axiom sin_PI2 : ``(sin (PI/2))==1``.
(**********)
+Lemma sin2_cos2 : (x:R) ``(Rsqr (sin x)) + (Rsqr (cos x))==1``.
+Intro; Unfold Rsqr; Rewrite Rplus_sym; Rewrite <- (cos_minus x x); Unfold Rminus; Rewrite Rplus_Ropp_r; Apply cos_0.
+Save.
+
+
+(**********)
Definition tan [x:R] : R := ``(sin x)/(cos x)``.
Lemma tan_plus : (x,y:R) ~``(cos x)==0`` -> ~``(cos y)==0`` -> ~``(cos (x+y))==0`` -> ~``1-(tan x)*(tan y)==0`` -> ``(tan (x+y))==((tan x)+(tan y))/(1-(tan x)*(tan y))``.