CBSE 2025 · Region 6 · Set 1 · Q6 · 1 mark
If $\displaystyle f(\mathrm{x})=\left\{\begin{array}{cc}\frac{\log (1+\mathrm{a} \mathrm{x})+\log (1-\mathrm{b} \mathrm{x})}{\mathrm{x}}, & \text { for } \mathrm{x} \neq 0 \\ k, & \text { for } \mathrm{x}=0\end{array}\right.$ is continuous at $\displaystyle \mathrm{x}=0$, then the value of k is :
Official answer
From CBSE’s own marking scheme for this paper.
(C)
$\displaystyle \mathrm{a}-\mathrm{b}$
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CBSE Class 12 Mathematics past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.