MCQ
The function $f(x) = \frac{{\log (1 + ax) - \log (1 - bx)}}{x}$ is not defined at $x = 0$. The value which should be assigned to f at $x =0$ so that it is continuos at $x = 0$, is
  • A
    $a - b$
  • $a + b$
  • C
    $\log a + \log b$
  • D
    $\log a - \log b$

Answer

Correct option: B.
$a + b$
b
(b) Since limit of a function is $a + b as $

as $x \to 0,$ therefore to be continuous at a function, its value must be

$a + b$ at $x = 0$ $ \Rightarrow \,\,f(0) = a + b.$

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