Trig help
posted by Kasey on .
How would I state the phase shift of y=cos(θpi/3) & then graph it?
Step by step would be awesome, I was out sick and needed to do a worksheet to catch up!

first make a sketch of y=cosθ
then translate it pi/3 radians to the right
in general for y=cos(θk) move y=cos(θ)to the right k radians
or for y=cos(θ+k) move y=cos(θ)to the left k radians
if there is a coefficient in front of the angle you have to factor out that coefficient to show the phase shift
e.g. y=cos(3θpi/2)
becomes y=cos3(θpi/6) , so the phase shift is pi/5 to the right 
last line should have said:
becomes y=cos3(θpi/6) , so the phase shift is pi/6 to the right
(keystroke error)