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Trigonometric Functions on Right Triangles definitions

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  • Trigonometric Function
    A mathematical ratio relating an angle of a right triangle to two of its sides, commonly used to solve for unknowns.
  • Sine
    A ratio comparing the length of the side opposite an angle to the hypotenuse in a right triangle.
  • Cosine
    A ratio comparing the length of the side adjacent to an angle to the hypotenuse in a right triangle.
  • Tangent
    A ratio comparing the length of the side opposite an angle to the side adjacent to that angle in a right triangle.
  • SOHCAHTOA
    A mnemonic device summarizing how sine, cosine, and tangent relate to the sides of a right triangle.
  • Reciprocal Identity
    A relationship where one trigonometric function is the flipped version of another, such as secant and cosine.
  • Cosecant
    A ratio representing the hypotenuse divided by the side opposite an angle in a right triangle.
  • Secant
    A ratio representing the hypotenuse divided by the side adjacent to an angle in a right triangle.
  • Cotangent
    A ratio comparing the length of the side adjacent to an angle to the side opposite that angle in a right triangle.
  • Inverse Trigonometric Function
    An operation that undoes a trigonometric function, allowing calculation of an angle from a given ratio.
  • Arc Function
    An alternative name for an inverse trigonometric function, often denoted with the prefix 'arc'.
  • Hypotenuse
    The longest side of a right triangle, always opposite the right angle.
  • Adjacent Side
    The side of a right triangle that forms the angle of interest, excluding the hypotenuse.
  • Opposite Side
    The side of a right triangle that does not form the angle of interest and is across from it.
  • Degree Mode
    A calculator setting used when angles are measured in degrees, essential for correct trigonometric calculations.
  • Radian Mode
    A calculator setting used when angles are measured in radians, necessary for certain trigonometric problems.