4.07: Cosine function and graph
The function is \(y=4\cos(x/8)+2\), with \(x\) in degrees.
(a)[1]
State the amplitude.
See the official mark scheme below.
(b)[1]
State the period in degrees.
See the official mark scheme below.
(c)[3]
Solve \(4\cos(x/8)+2=0\) for \(-1080^\circ\leqslant x\leqslant1080^\circ\).
See the official mark scheme below.
(d)[2]
Sketch the graph on the given interval.
See the official mark scheme below.
