If f(x)=(4x^3−2)/(x^4), find f'(x), find f'(3)

Answer 1

f(x) = (4x^3 -2)/(x^4)

= 4x^-1 - 2x^-4

f'(x) = -4/x^2 + 8/x^5

f'(3) = -4/(3^2) + 8/(3^5)

f'(3) = -4/9 + 8/243

= 8/243 - 108/243

= -100/243 = about -0.412