The Student Room Group

f”(x)

If f”(x) = 0 and there’s a change of sign either side of the x value then there’s a point of inflection

What do we get if we had f”(x) = 0 and either side of the x value were positive values? Would that be a minima?

For negative values, would that be a maxima?
Reply 1
x + x^4 satisfies your conditions at x=0 but is not even stationary there.

Quick Reply