Exercises 7 and 8 refer to the curves in the given figure.
[-4.7, 4.7] by [-3.1, 3.1]
(a)
[-4.7, 4.7] by [-3.1, 3.1]
(b)
8. Use trigonometric identities to explain which of these curves is the graph of r=6cos2θsin2θ.