From f5c160af4132a3b121aa6f699ed7474044aa4427 Mon Sep 17 00:00:00 2001
From: James Su <amagicalsoup@gmail.com>
Date: Thu, 14 Nov 2019 14:51:48 +0000
Subject: [PATCH] Update Trig Quiz 1.md

---
 Grade 10/Math/MPM2DZ/Trig Quiz 1.md | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Grade 10/Math/MPM2DZ/Trig Quiz 1.md b/Grade 10/Math/MPM2DZ/Trig Quiz 1.md
index 5c4809c..e44a286 100644
--- a/Grade 10/Math/MPM2DZ/Trig Quiz 1.md	
+++ b/Grade 10/Math/MPM2DZ/Trig Quiz 1.md	
@@ -102,6 +102,9 @@ $`\cos(\beta) = \dfrac{AF}{AE} = \dfrac{AF}{1} = AF`$
 
 $`\text{Draw a parallel line to } CD \text{ that connects point } E \text{ to } AD. \quad \cos(\alpha + \beta) = \dfrac{BE}{AE} = \dfrac{BE}{1} = BE`$
 
+$`\therefore \sin(\alpha + \beta) = CD = CF + FD = \cos(\alpha) \sin(\beta) + \sin(\alpha) + \cos(\beta)`$
+
+$`\therefore \cos(\alpha + \beta) = BE = \cos(\alpha - \beta)`$
 ## Footer Notes
 
 $`\text{ASTT} = \text{ Angle Sum Of Triangle Theorem}`$