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If $f(x) = \dfrac{\log(1+ax) - \log(1-bx)}{x}$ for $x \neq 0$ and $f(0) = k$, and $f(x)$ is continuous at $x = 0$, then $k$ equals
If $f(x) = \dfrac{\log(1+ax) - \log(1-bx)}{x}$ for $x \neq 0$ and $f(0) = k$, and $f(x)$ is continuous at $x = 0$, then $k$ equals
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Standard limit: $\displaystyle\lim_{x \to 0}\frac{\ln(1+px)}{x} = p$. Apply this separately to each logarithmic term.
Updated On: Apr 8, 2026
- $a + b$
- $a - b$
- $a$
- $b$
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The Correct Option is A
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