Question

Answer 1

Bài 5:

\(g\left(x\right)=x^3-6x^2+9x+2\)

=>\(g'\left(x\right)=3x^2-6\cdot2x+9=3x^2-12x+9\)

Đặt g'(x)=0

=>\(3x^2-12x+9=0\)

=>\(x^2-4x+3=0\)

=>(x-1)(x-3)=0

=>\(\left[{}\begin{matrix}x=1\\x=3\end{matrix}\right.\)

\(g\left(1\right)=1^3-6\cdot1^2+9\cdot1+2=5\)

\(g\left(0\right)=0^3-6\cdot0^2+9\cdot0+2=2\)

\(g\left(3\right)=3^3-6\cdot3^2+9\cdot3+2=2\)

Vậy: GTLN là 5, GTNN là 2