Determine length of the arc intercepted by the central angle of Π/ 4 radians in the circle of radius 3.2 inches. Use formula s = r Θ. Function y = A cos ( B x - C) + D, amplitude is | A |, period is 2Π / B, phase shift ( horizontal) is C / B and vertical shift is D. Determine horizontal shift of function. y = - 5 + 2 cos (2 x + Π/3).