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Defining the Unit Circle definitions

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  • Unit Circle
    A circle centered at the origin with a radius of 1, used to relate angles to coordinates and trigonometric values.
  • Radius
    The fixed distance from the center of a circle to any point on its edge; equals 1 in the unit circle.
  • Origin
    The point (0, 0) on a coordinate plane where the unit circle is centered.
  • Degree
    A unit for measuring angles, with a full circle containing 360 of these.
  • Radian
    A unit for measuring angles based on arc length, with a full circle containing 2π of these.
  • Coordinate
    An ordered pair (x, y) representing a point's position on the unit circle.
  • Equation of the Unit Circle
    The relationship x² + y² = 1, satisfied by all points on the unit circle.
  • Quadrant
    One of four sections of the coordinate plane, each containing part of the unit circle.
  • Ordered Pair
    A set of two numbers (x, y) indicating a point's location, such as those corresponding to angles on the unit circle.
  • Full Rotation
    A complete turn around the circle, equivalent to 360 degrees or 2π radians.
  • π (Pi)
    A mathematical constant representing the ratio of a circle's circumference to its diameter, used in radian measures.
  • Verification
    The process of checking if a point lies on the unit circle by substituting its coordinates into x² + y² = 1.
  • Angle Measure
    The size of an angle, often given in degrees or radians, corresponding to a specific point on the unit circle.
  • Trigonometry
    A branch of mathematics dealing with relationships between angles and sides, heavily utilizing the unit circle.
  • Rotation
    Movement around the center of the unit circle, described by increasing angle measures.