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The Sine Rule, Cosine Rule and Area of a Triangle | Year 1 Pure | A Level Maths

The sine rule, cosine rule and area formula extend trigonometry to any triangle and feature in many exam questions. In this lesson you will learn how to apply a/sin(A) = b/sin(B) = c/sin(C), the cosine rule a^2 = b^2 + c^2 — 2bc cos(A), and the area formula (1/2) ab sin(C), including handling the ambiguous case of the sine rule. These tools are also essential in mechanics for resolving forces and in vector problems involving angles.

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Stage 4

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Lesson Video On The Sine Rule, Cosine Rule and Area of a Triangle

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Lesson Resources For The Sine Rule, Cosine Rule and Area of a Triangle

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