Egbert is unwinding tape from a circular dispenser of radius a by holding the tape taut...

Egbert is unwinding tape from a circular dispenser of radius a by holding the tape taut and perpendicular to the dispenser. Find a set of parametric equations for the path traced by the end of the tape (the point P in Figure 1.35) as Egbert unwinds the tape. Use the angle θ between and the positive x-axis for parameter. Assume that little enough tape is unwound so that the radius of the dispenser remains constant.