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Law of Cosines definitions

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  • Law of Cosines
    A set of equations relating the squares of triangle sides to a known angle, used when the law of sines is not applicable.
  • SAS Triangle
    A triangle where two sides and the included angle are known, allowing use of the law of cosines to find the third side.
  • SSS Triangle
    A triangle where all three sides are known, enabling calculation of any angle using the law of cosines.
  • Included Angle
    The angle formed between two known sides in a triangle, essential for applying the law of cosines in SAS cases.
  • Cosine
    A trigonometric function used in the law of cosines to relate side lengths and angles in a triangle.
  • Ambiguity
    A situation in triangle solving where more than one solution for an angle exists, avoided when using the law of cosines.
  • Pythagorean Theorem
    A special case of the law of cosines where the included angle is 90 degrees, simplifying the formula.
  • Angle Sum Formula
    The rule stating that the interior angles of a triangle always add up to 180 degrees.
  • Inverse Cosine
    A function used to determine an angle from its cosine value, yielding a unique result between 0 and 180 degrees.
  • Corresponding Side
    The side in a triangle that is opposite a specific angle, crucial for setting up equations in the law of cosines.
  • Rounding Error
    A small inaccuracy introduced when approximating values, minimized by keeping calculations in exact form.
  • Plug and Chug
    A straightforward calculation process where known values are substituted directly into a formula.
  • Variation
    A specific form of the law of cosines equation, chosen based on which side or angle is being solved for.
  • Triangle Solving
    The process of finding unknown sides and angles in a triangle using trigonometric laws and formulas.
  • Known Angle
    An angle in a triangle whose measure is provided, allowing the application of the law of cosines.