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Let RR and QQ be the sets of real number...

Let `RR` and` QQ` be the sets of real numbers and rational numbers respectively. If `a in QQ` and f: `RR rarr RR` is defined by ,
`f(x)={(x " when" x in QQ ),(a-x" when " x notin QQ ):}`
then show that ,`(f o f ) (x) = x`, for all `x in RR`

Text Solution

Verified by Experts

The correct Answer is:
`=x "for all" x in RR`
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