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Given the Function F ( X ) = 1 X + 2 . Find the Points of Discontinuity of the Function F(F(X)). - Mathematics

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Question

Given the function  
\[f\left( x \right) = \frac{1}{x + 2}\] . Find the points of discontinuity of the function f(f(x)).
Sum

Solution

\[f\left[ f\left( x \right) \right] = \frac{1}{\frac{1}{x + 2} + 2} = \frac{x + 2}{2x + 5}\]
\[So, f\left[ f\left( x \right) \right] \text{is not defined at } x + 2 = 0 \text{ and } 2x + 5 = 0\]
\[\text{ If x + 2 = , then }  x = - 2\]
\[\text{ If 2x + 5 = 0, then } x = - \frac{5}{2}\]
Hence, the function is discontinuous at
\[x = - \frac{5}{2} \text{ and }  - 2\]
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Chapter 9: Continuity - Exercise 9.2 [Page 37]

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RD Sharma Mathematics [English] Class 12
Chapter 9 Continuity
Exercise 9.2 | Q 18 | Page 37

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