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Law of Cosines definitions

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  • Law of Cosines
    Relates the squares of three triangle sides to a known angle, enabling solutions for sides or angles when Law of Sines is not applicable.
  • SAS Triangle
    A triangle configuration with two sides and the included angle known, ideal for applying the Law of Cosines.
  • SSS Triangle
    A triangle configuration where all three sides are known, allowing calculation of any angle using the Law of Cosines.
  • Cosine
    A trigonometric function used in the Law of Cosines to relate side lengths and angles in non-right triangles.
  • Inverse Cosine
    A function yielding a unique angle between 0 and 180 degrees, eliminating ambiguity when solving for triangle angles.
  • Angle Sum Property
    A rule stating that the sum of a triangle's interior angles is always 180 degrees, used to find the final unknown angle.
  • Plug and Chug
    A calculation method where known values are substituted directly into formulas for straightforward solutions.
  • Rounding Error
    A numerical inaccuracy that can accumulate when approximating values, minimized by keeping results in square root form.
  • Square Root Form
    An exact representation of a value, preferred in intermediate steps to reduce rounding errors in multi-step calculations.
  • Pythagorean Theorem
    A special case of the Law of Cosines applicable to right triangles, where the cosine term becomes zero.
  • Corresponding Angle
    An angle directly opposite a specific side in a triangle, essential for setting up the Law of Cosines formula.
  • Triangle Side
    A segment connecting two vertices, whose length can be determined using the Law of Cosines when certain angles are known.
  • Triangle Angle
    The measure between two sides, calculable with the Law of Cosines if all three sides are known.
  • Variable
    A symbol representing an unknown side or angle in triangle equations, solved using trigonometric laws.
  • Formula Variation
    Different forms of the Law of Cosines equation, chosen based on which side or angle is being solved.