The function f(x)=2x321x2+36x+9\displaystyle {f{{\left({x}\right)}}}={2}{x}^{{3}}-{21}{x}^{{2}}+{36}{x}+{9} has one local minimum and one local maximum.
This function has a local minimum at x\displaystyle {x} equals  

with value  


and a local maximum at x\displaystyle {x} equals  

with value