f(theta)=costheta

1- complete the table using the unit circle and sketch thr graph theta= -360 ,-270 ,-180 ,-90 ,0 ,90 ,180 ,270 ,360 . f(theta)= 2- state the coordinates of the maximum and manimum valuas of f(theta)=costheta within the domaine of the table? 3- what are the coordinates of the zeros of the functoin within this domain? 4- show that f(theta)=f(-theta) for all values of theta in the table? 5- explain why f(theta)=f(-theta)for all theta ?