Calculus

How to solve

f'' > 0 means concave up; f'' < 0 means concave down. Inflection where f'' changes sign.

Steps

  1. Compute f''.
  2. Evaluate the sign, or solve f''=0 for inflection.

Example

f(x)=x³−3x

  1. f''=6x.
  2. Inflection at 0; concave up for x>0.

Answer: 0 or up/down

How to type answers

  • Enter up, down, or an x-value
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