UNIT TWO: SINUSOIDAL FUNCTIONS
Lesson One: The Unit Circle and The Graphs of y  sin x and y  cos x
Write down your special triangles here:
If we want the hypotenuse equal to one in both triangles, the
following results……
1
1
Suppose we “graphed” one of the special triangles onto the unit circ le, so that the hypotenuse lined up
with the radius (which equals one).
1
45°
Then we can find the coordinates of each point on the circle using the relationship we learned in unit one:
y
r
x
cos  
r
sin  
BUT r=1 (b/c it’s a UNIT circle)
 sin   y and cos   x
or
 x, y   cos  , sin  
Using the UNIT CIRCLE HANDOUT, and your “adjusted” special triangles, write down the ordered pairs
for each SPECIAL angle from 0° to 360°.
Now continue with P. 24 #2, #4, #6