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


f(x)=x3-6x2+9x+10


f’(x)=3x2-12x+9


f’(x)=3(x2-4x+3)


=3(x-3)(x-1)



Function f(x) is decreasing for x [1,3] and increasing in x (-∞,1) (3, ∞)


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