$f(x)=4 \log _{e}(x-1)-2 x^{2}+4 x+5, x>1$,which one of the following is $NOT$ correct?

  • A
    $f$ is increasing in $(1,2)$ and decreasing in $(2, \infty)$
  • B
    $f(x)=-1$ has exactly two solutions
  • C
    $f'(e) - f''(2) < 0$
  • D
    $f(x)=0$ has a root in the interval $(e, e+1)$

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