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Given the function f(x) = 1x+2. Find the points of discontinuity of the composite function y = f(f(x)) - Mathematics

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प्रश्न

Given the function f(x) = `1/(x + 2)`. Find the points of discontinuity of the composite function y = f(f(x))

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उत्तर

f(x) = `1/(x + 2)`

f[f(x)] = `1/("f"(x) + 2)`

= `1/(1/(x + 2) + 2)`

= `1/((1 + 2x + 4)/(x + 2))`

= `(x + 2)/(2x + 5)`

∴ f[f(x)] = `(x + 2)/(2x + 5)`

This function will not be defined and continuous where 2x + 5 = 0

⇒ x = `(-5)/2`.

Hence, x = `(-5)/2` is the point of discontinuity.

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अध्याय 5: Continuity And Differentiability - Exercise [पृष्ठ १०८]

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एनसीईआरटी एक्झांप्लर Mathematics [English] Class 12
अध्याय 5 Continuity And Differentiability
Exercise | Q 17 | पृष्ठ १०८

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