
The graph shows .
Find the value of and the value of .
Extract:
Oscillating graph on a set of axes, x axis from 0 to 360 and y axis from -3 to 3. Graph goes through the points (0,3), (90,-3), (180,3), (270,-3) and (360,3). The graph shows f(x) = a cos(bx).
Write down the period of .











