Higher Education, Mathematics, Calculus, Geometry, Trigonometry
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Ohio Open Ed Collaborative
Law of Cosines, Law of Sines, Mathematics, Similar Triangles, Tmm0022
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Education Standards (1)

Law of Sines


Law of Sines

TMM 002 PRECALCULUS (Revised March 21, 2017)

2c. Analyze general triangles. Routine analysis of side lengths and angle measurements using trigonometric ratios/functions, as well as other relationships.*
Sample Tasks:

  • The student can solve general triangles using trigonometric ratios and relationships including laws of sine and cosine.
  • The student can compare similar triangles.
  • The student can compute length and angle measurements inside complex drawings involving multiple geometric objects.
  • The student can algebraically describe relationships inside complex drawings involving multiple geometric objects.

Law of Sines

Triangulation is the method of measuring remaining sides and/or angles of a triangle given partial information about some sides/angles of the triangle. The law of sines is useful when the partial specification is in the form of AAS, ASA, SSA. The first two specifications define a unique triangle. However, the last case has between 0 to 2 multiple answers, depending on the given information. It can be shown that the common value of three ratios considered in the law of sines is the diameter of the circumcircle of the triangle.


Review: Properties of similar triangles, solving equations of proportions

Learning Objectives:

  • Law of Sines