Question

@inkyvoyd helpp

Answer 1

i looked at the sheet is there any information?

Answer 2

take second derivative and let it =0 to find x , that is the result

Answer 3

\[f(x)=3x ^{3}+18x ^{2}-3x+4\]
\[f ^{'}(x)=9x ^{2}+36x-3\]
\[f ^{''}(x)=18x+36=0\]
\[x=\frac{ -36 }{ 18 }=-2\]