Definitions
Trigonometric Functions
The Unit Circle
Radians and Degrees: Radians are the units of angles. Degrees are units of measurement of angles
Cosine: Adjacent side of triangle/ Hypotenuse side of triangle
Tangent: Opposite side of triangle/ Adjacent side of triangle
How to convert from one set of units to another:
-Write the conversion as a fraction
-Multiply
-Cancel any units that are both top and bottom
Terminal, co-terminal, and reference angles: Terminal side is a straight line that has been rotated around a point on another line to form an angle measured in a clockwise or counterclockwise direction. Co-terminal angles are angles who share the same initial side and terminal sides. Reference angles are the smallest angles between the terminal side and the x-axis.
The line where it says 30 degrees is the co-terminal angle. The reference angle is 30 degrees. The terminal side is 390 degrees.
Cosecant: Reciprical of Sine
Positive and Negative angles: Negative angles are a way of measuring an angle from a different direction. A positive angle is created by rotating counter-clockwise around the origin of a coordinate system, starting at the x-axis (the horizontal axis) and proceeding through the quadrants in the order I, II, III, IV.
Secant: The Reciprocal of a Cosine.
Cotangent:Reciprocal of Tangent
Examples of radians and degrees:
Example of positive and negative angles:
The unit circle is the circle of radius one centered at the origin (0, 0) in the Cartesian coordinate system in the Euclidean plane.
Sine: Opposite side of triangle/ Hypotenuse side of triangle
Trigonometric Functions: Degrees of the unit circle^
Trigonometric Functions: Radians of the unit circle^
45-45-90 triangle
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Real World example:
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Relationship map between 6 trig functions
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example of 6 trig functions for both 45-45-90 and
30-60-90
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