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The function f(x) = 4-x24x-x3 is ______. - Mathematics

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Question

The function f(x) = `(4 - x^2)/(4x - x^3)` is ______.

Options

  • Discontinuous at only one point

  • Discontinuous at exactly two points

  • Discontinuous at exactly three points

  • None of these

MCQ
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Solution

The function f(x) = `(4 - x^2)/(4x - x^3)` is discontinuous at exactly three points.

Explanation:

Given that: f(x) = `(4 - x^2)/(4x - x^3)` 

For discontinuous function

4x – x3 = 0

⇒ x(4 – x2) = 0

⇒ x(2 – x)(2 + x) = 0

⇒ x = 0, x = – 2, x = 2

Hence, the given function is discontinuous exactly at three points.

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Chapter 5: Continuity And Differentiability - Exercise [Page 113]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 5 Continuity And Differentiability
Exercise | Q 84 | Page 113

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