Find the intervals of monotonicities and hence find the local extremum for the following functions: f(x)=2x3+3x2-12x

Find the intervals of monotonicities and
hence find the local extremum for the
following functions: $f (x) = 2 x^{3} + 3 x^{2} - 12 x$

Matching exercise

Match the items on the right to the items on the left.

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