Method

Part of Sine Rule · Section 3 of 5

Deep DiveUnit: Geometry & MeasuresGCSE

This deep dive covers Method within Sine Rule for GCSE Mathematics. Revise Sine Rule in Geometry & Measures for GCSE Mathematics with 12 exam-style questions and 3 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 3 of 5 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.

Method

1 Label sides a, b, c opposite to angles A, B, C
2 Check you have a matched pair (side + opposite angle)
3 Set up the equation using only the two ratios you need
4 Cross-multiply and solve

Practice questions for Sine Rule

Which of the following is the sine rule?

  • A. a/sinA = b/sinB = c/sinC
  • B. a² = b² + c² − 2bc cosA
  • C. Area = ½ab sinC
  • D. sinA/a = sinB/b + sinC/c
1 markfoundation

Explain what is meant by the ambiguous case of the sine rule, and state when it can occur.

3 markshigher

Quick recall flashcards

Sine Rule
a/sinA = b/sinB = c/sinC. Use when you have a matched pair (side with opposite angle).
Sine Rule
a/sin A = b/sin B = c/sin C

12 questions on Sine Rule — practise free

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