MCQ
For the function $f(x) = x^4 (12 ln x - 7)$
  • A
    the point $(1, - 7)$ is the point of inflection
  • B
    $x = e^{1/3}$ is the point of minima
  • C
    the graph is concave downwards in $(0, 1)$
  • All of the above

Answer

Correct option: D.
All of the above
d
$\frac{{dy}}{{dx}}= 16 x^3 (3 ln x - 1) $

 $\frac{{d^2y}}{{dx^2}} = x^2 (9 ln x) $

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