Answer:
C
Step-by-step explanation:
From the graph you can see that y changes from -2 to 2, so the range of the function is [tex][-2,2].[/tex]
Since the range of the functions [tex]y=\cos x[/tex] and [tex]y=\sin x[/tex] is [tex][-1,1][/tex] and the range of the functions [tex]y=k\cos x[/tex] and [tex]y=k\sin x[/tex] is [tex][-k,k],[/tex] we can state that the correct option is C: [tex]f(t)=-2\cos 3t.[/tex]
Check the value at t=0:
[tex]f(0)=-2\cos 3\cdot 0=-2\cos 0=-2.[/tex]
