7. h(x) = = =sin-¹(x) 8. Using derivative rules and the trigonometric identities 1 sin² (8) = (1 - cos(20)), cos² (0) = (1 + cos(20)), show clearly that the function

f(x) = sin(x) cos(x) — satisfies properties (a) and (b). 2 (a) f'(x) = cos(2x), (b) ƒ ( 7 ) = 0