
Patrick B. answered 11/23/20
Math and computer tutor/teacher
(a)
quotient rule says:
g f' - f g' / g^2
(4*6 - -5*8)/ (4^2)
(24 - -40)/16
66/16
33/8
(b) y = f(x)
f(9) = 4
G(x)= ln y = ln f(x)
G'(x)= dG/dx = f'(x) / f(x)
-3 = f'(9)/f(9)
-3 = f'(9) / 4
12 = f'(9) = dy/dx