Find the intervals on which each of the following functions is (a) increasing (b) decreasing.


f(x)=x3-12x2+36x+17


f’(x)=3x2-24x+36


f’(x)=3(x2-8x+12)


=3(x-6)(x-2)



Function f(x) is decreasing for x [2,6] and increasing in x (-∞,2) (6, ∞)


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