Graphs of Sine and Cosine

Parent Function Graph y=cosx

The Graph of Cosine shows the cosine value for different radian measurements on the Unit Circle. The beginning and end of a cosine graph is at the maximum y-value. The graph reaches the minimum y-value at the half-way point. This graph shows that at a value of 0 radians the cosine value of that
angle on the unit circle is 1, at 1/2π radians the cosine function of that
angle is 0 on the unit circle, etc.

y=AcosB(x-C)+D

A= Amplitude (Vertical Stretch or Shrink)

B= Horizontal Stretch or Shrink

C= Horizontal Shift

D= Vertical Shift

Steps for Graphing the Cosine Function:

1. Always start with D to determine the sinusoidal axis

-In the graph above, D=0, therefore the sinusoidal axis is at 0 on the y-axis

2. Determine the Amplitude

-Plot the maximum and minimum y values of your graph

-In this graph, the amplitude is 1 because A=1

3. Determine the period

-To find the period use the equation 2π/B

-The period here is 2π because B=1

4.Graph

-The graph above is graphed

5. Label Axis

-Y-axis and X-axis

http://www.youtube.com/watch?v=CrdsJzpRgYE&feature=youtube_gdata_player

y=AcosB(x-C)+D

A= Amplitude (Vertical Stretch or Shrink)

B= Horizontal Stretch or Shrink

C= Horizontal Shift

D= Vertical Shift

Steps for Graphing the Cosine Function:

1. Always start with D to determine the sinusoidal axis

-In the graph above, D=0, therefore the sinusoidal axis is at 0 on the y-axis

2. Determine the Amplitude

-Plot the maximum and minimum y values of your graph

-In this graph, the amplitude is 1 because A=1

3. Determine the period

-To find the period use the equation 2π/B

-The period here is 2π because B=1

4.Graph

-The graph above is graphed

5. Label Axis

-Y-axis and X-axis

http://www.youtube.com/watch?v=CrdsJzpRgYE&feature=youtube_gdata_player