# Cosine Rule – Finding Angles

Students learn how to derive and apply the Cosine Rule to find missing angles in triangles.  As learning progresses students begin to calculate a combination of angles in adjoining triangles.
##### Differentiated Learning Objectives
• All students should be able to calculate an unknown angle in a triangle using the Cosine rule.
• Most students should be able to calculate an unknown angle or a bearing using the Cosine rule.
• Some students should be able to derive and apply the Cosine rule for triangular shapes.

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