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If f(x) = log |x| then for x ne 0 f(x)...

If f(x) = log |x| then for ` x ne 0 ` f(x) is equal to

A

`(1)/(|x|)`

B

`(1)/(x)`

C

`-(1)/(x)`

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
B
We have,
`f(x)=log|x|={{:(logx" ,",xgt0),(log(-x)",",xlt0):}`
`:." "f'(x)={{:(" "(1)/(x)" ,",xgt0),(-(1)/(x)xx(-1)=(1)/(x)",",xlt0):}`
`implies" "f'(x)=(1)/(x)" for all "xne0.`
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