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Let `f: R->R` whre `R^+` is the set of all positive real numbers, be such that `f(x)=(log)_e xdot` Determine: `{x :f(x)=-2}`

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Given,`f(x)=(log)_e x....(i)`
`f(x)=-2....(ii)`
comparing (i) and (ii) we get
`(log)_e x=-2`
=`x=e^(-2)`
`x=e^(-2)`
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