Question 980208


The turning point of a function is the point where the derivative of the function is equal to zero.


The derivative of the function  {{{y}}} = {{{3x³ - 6x² -9}}}  is  {{{3*3x^2 - 6*2x}}} = {{{9x^2 - 12x}}}. 

So, &nbsp;its turning points are those where the coordinate &nbsp;(variable)&nbsp; <B>x</B> satisfies the equation 


{{{9x^2 - 12x}}} = {{{0}}}.


They are &nbsp;{{{x[1]}}} = {{{0}}}&nbsp; and &nbsp;{{{x[2]}}} = {{{12/9}}} = {{{4/3}}}. 


The points &nbsp;({{{x[1]}}},{{{f(x[1])}}})&nbsp; and &nbsp;({{{x[2]}}},{{{f(x[2])}}})&nbsp; are yours turning points.


Calculate yourself the values of &nbsp;{{{f(x[1])}}}&nbsp; and &nbsp;{{{f(x[2])}}}.