Cubic function

In mathematics, a cubic function is a function of the form

Derivative

The derivative f'(x)=3ax^2+2bx+c, will yield

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x=rac{-b pm sqrt {b^2-3ac }}{3a}

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when f'(x)=0,. Bearing its resemblance to the quadratic formula, this formula can be used to find the critical points of a cubic function. It turns out that, if

Related Topics:
Quadratic formula - Critical points

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b^2-3ac > 0,

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, then the cubic function will have two critical points

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— a local maximum and a local minimum; if

Related Topics:
Local maximum - Local minimum

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b^2-3ac leq 0,

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, then there are no critical points.

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