Asked by Destiny

find the intervals on which the function is increasing or decreasing and find any relative minima or maxima.
f(x)=0.2x^3-0.2x^2-5x-4
Answered by Steve
f=1/5 (x+4)(x^2 - 5x - 5)
f' = .6x^2 - .4x - 5
f'=0 at x = 1/3 (1 ± 2√19)

f increases where f' > 0