# Different Interpretations of Trigonometric Functions, Fall 2014

Different Interpretations of Trigonometric Functions, Fall 2014
A.
B.
C.
D.
Setting/Picture
Unit Circle, (a,b) is the
point where the angle
intersects the unit circle
Circle with center (0,0),
point where the angle
intersects the circle
cos()
sin()
A. is like B. with r=1
B. is like C, but you
based on which
terminal side of the
angle is in.
C. is like B. with all
triangles in
input: angle in standard position
input: angle in standard position
output: a (the x-coordinate)
output: b (the y-coordinate)
input: angle in standard position
input: angle in standard position
output: the ratio
output: the ratio
Ratios of x-, ycoordinates and/or
circle:
input: an angle between 0 and 90
input: an angle between 0 and 90
Ratios of sides of
the triangle:
output: ratio of sides of a right
triangle,
output: ratio of sides of a right
triangle
input: any real number
Similar to cosine
Right Triangle
Graph on coordinate
plane
Other trig functions
Obtained from sine
and cosine:
output: the real number obtained
by computing cosine (use method