Figure 2To graph a trigonometric function, put the angles (usually in radians) on the x-axis and the results of
applying the function on the y-axis. You can always use your graphing calculator (if you have one
and know how to use it) to find the graph of a trigonometric function. That would be one way to do
Example 4.
But ultimately you’re better off if you can have a true understanding, a “feeling,” for what the
graphs of trigonometric functions look like. The way to do that is to start with a picture in your mind
of what the graphs of the three basic functions look like.
Basic trig function 1: The graph of y = sin x is a curve that goes through the origin because sin 0 = 0
and rises to a crest at because sin
1. Which of the following is an equation of the graph shown in Figure 2?(A)
(B)
(C)
(D)
(E) y = 2cos2x