Solution
For this case we can verify the answer using the point x= 0 if we replace we got:
y=8 cos (pi/40* 0) = 8 cos (0) = 8
y= -8 sin (pi/40 *0)= -8 sin(0) = 0
y= -8cos(pi/40*0)= -8 cos (0)= -8
y= 8 sin (pi/40 *0)= 8 sin(0) = 0
Then the correct option would be:
y= -8cos(pi/40*0)
