Chapter 13 More Trigonometry

# 13.6 The Cosine Rule and 2D Trigonometric Problems

The cosine rule a^2=b^2+c^2-2bccosA can be used in any triangle to calculate an unknown side. In this section, we learn about sine and cosine rules, cosine rule, arrange the cosine rule to find an angle, use the cosine rule to find the missing angle.

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The cosine rule Â can be used in any triangle to calculate an unknown side. In this section, we learn about sine and cosine rules, cosine rule, arrange the cosine rule to find an angle, use the cosine rule to find the missing angle.

Using the cosine rule to solve 2D problems.

The Cosine Rule and 2D Trigonometric Problems - Sine and cosine rules, cosine rule, arrange the cosine rule to find an angle, use the cosine rule to find the missing angle.