Mathematical Methods Β· Unit 4 Β· Trigonometry Β· Cosine and sine rules
Use the formula area = 1 2 π π sin (π΄) to calculate the area of a triangle.
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Use the cosine rule, π2 = π2 + π2 β 2ππ cos(πΆ).
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Use the sine rule (ambiguous case is required), π sin(π΄) = π sin(π΅) = π sin(πΆ), where π, π and π are the side lengths of the triangle and π΄, π΅ and πΆ are the corresponding opposite angles.