Critical points calculator

Find all critical points of a function and classify them as maxima, minima, or inflection points using derivative tests.

f(x) =

What are critical points?

Critical points occur where f'(x) = 0 or f'(x) is undefined. They are candidates for local maxima, minima, or neither (inflection points).

Classification using the second derivative test

f''(c) > 0: Local minimum at x = c (concave up).

f''(c) < 0: Local maximum at x = c (concave down).

f''(c) = 0: Inconclusive — use first derivative test or higher-order derivatives.

Inflection points

Points where concavity changes (f'' changes sign). These occur where f''(x) = 0 and f'' actually changes sign.

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