MCQ
${d \over {dx}}\log |x|{\rm{ }} = ......,(x \ne 0)$
  • ${1 \over x}$
  • B
    $ - {1 \over x}$
  • C
    $x$
  • D
    $ - x$

Answer

Correct option: A.
${1 \over x}$
a
(a) $\log |x|\, = \log x$, if $x > 0$$ = \log ( - x)$, if $x < 0$ 

Hence $\frac{d}{{dx}}\left\{ {\log |x|} \right\} = \frac{1}{x}$, if $x > 0$

$ = \left( {\frac{1}{{ - x}}} \right)( - 1) = \frac{1}{x}$, if $x < 0$

Thus $\frac{d}{{dx}}\left\{ {\log |x|} \right\} = \frac{1}{x}$, if $x \ne 0$.

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