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Write the Domain of the Real Function `F (X) = Sqrt([X] - X) .`

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Question

Write the domain of the real function

`f (x) = sqrt([x] - x) .`

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Solution

[x] is the greatest integer function.

\[\left[ x \right] \leq x, \forall x \in R\]
\[ \Rightarrow \left[ x \right] - x \leq 0, \forall x \in R\]
\[ \Rightarrow \sqrt{\left[ x \right] - x} \text{ does not exist for anyx} \in R . \]
\[\text{Domain} =\phi\]

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Chapter 2: Functions - Exercise 2.5 [Page 74]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 2 Functions
Exercise 2.5 | Q 29 | Page 74

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