The MATLAB Notebook v1.6

Note that at x = 0, the derivative vanishes. But the function neither takes a minima or a maxima at x = 0, as is plotted below. x= -5:0.1:5; f =3*x.^3 -9; plot(x,f); grid on; So, let us separate out the issues: Points where the derivative of a function vanishes are called . STATIONARY points ................
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