<Ul> <Li> If f' ' (x) <0, the stationary point at x is concave down; a maximal extremum . </Li> <Li> If f' ' (x)> 0, the stationary point at x is concave up; a minimal extremum . </Li> <Li> If f' ' (x) = 0, the nature of the stationary point must be determined by way of other means, often by noting a sign change around that point . </Li> </Ul> <Li> If f' ' (x) <0, the stationary point at x is concave down; a maximal extremum . </Li> <Li> If f' ' (x)> 0, the stationary point at x is concave up; a minimal extremum . </Li> <Li> If f' ' (x) = 0, the nature of the stationary point must be determined by way of other means, often by noting a sign change around that point . </Li>

Explain why the curve has no stationary points