Cosine Rule
Mathematics · Secondary 3 · Trigonometry and Mensuration · Semester 2

Cosine Rule

Applying the Cosine Rule to solve for sides and angles in any triangle.

MOE Syllabus OutcomesMOE: Geometry and Measurement - S3MOE: Trigonometry - S3

About This Topic

Applying the Cosine Rule to solve for sides and angles in any triangle.

Key Questions

  1. Explain the derivation of the Cosine Rule and its relationship to Pythagoras' theorem.
  2. Differentiate between scenarios where the Sine Rule is more efficient and where the Cosine Rule is necessary.
  3. Construct a problem that requires the use of the Cosine Rule to find an angle.

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Edited by Adriana Perusin, Editor-in-Chief, Flip Education
Synthesized by Flip Education from Lyman's Think-Pair-Share collaborative-discussion routine (1981)