Answer:
y=4sin(1/4x)
Explanation:
1. Either sin or cos graph
y=asin(b(x-c))+d or y=acos(b(x-c))+d
a = amplitude
b = period (2π/b = answer)
c = x-shift (negative)
d = y-shift (positive)
2. Graph each possibility
a = 4
b = 2π/8π = 1/4
c = 0
d = 0
y=4sin(1/4x) or y=4cos(1/4x)