Cosine Rule – Finding Lengths

Cosine Rule – Finding Lengths
Cosine Rule – Finding Lengths
Cosine Rule – Finding Lengths
Cosine Rule – Finding Lengths

              Cosine Rule – Finding Lengths

              Students learn how to derive and apply the Cosine rule to find missing lengths in triangles.  As learning progresses they are challenged to apply multiple formulae involving triangles to solve more complex problems.
              Differentiated Learning Objectives
              • All students should be able to calculate an unknown length in a non right-angled triangle using the Cosine rule.
              • Most students should be able to calculate a magnitude of direction using bearings and a length in a non right-angled triangle using the Cosine rule.
              • Some students should be able to derive and apply the Cosine Rule to calculate unknown lengths in triangle shapes.
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              Scheme of Work Link
              Trigonometry - Non-Right-Angled Triangles
              Related Blog
              Solving Problems with Non-Right-Angled Triangles 
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