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Black Book Advanced Problems in MathematicsMathematicsContinuity and Differentiability

If f(x) has isolated point of discontinuity at x = a such that |f(x)| is continuous at x = a then :

Options

  1. A_ x a f(x) does not exist
  2. B_ x a f(x) + f(a) = 0
  3. Cf(a) = 0
  4. DNone of these

Correct answer

B. _ x a f(x) + f(a) = 0

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