CBSE 2025 · Region 1 · Set 2 · Q20 · 1 mark
Assertion (A) : $\displaystyle f(x)=\left\{\begin{array}{cc}3 x-8, & x \leq 5 \\ 2 \mathrm{k}, & x>5\end{array}\right.$ is continuous at $\displaystyle x=5$ for $\displaystyle \mathrm{k}=\frac{5}{2}$.
Reason (R) : For a function $\displaystyle f$ to be continuous at $\displaystyle x=a$, \[\lim _{x \rightarrow a^{-}} f(x)=\lim _{x \rightarrow a^{+}} f(x)=f(a) \]
Official answer
From CBSE’s own marking scheme for this paper.
(D)
Assertion (A) is false, but Reason (R) is true.
Continuity and DifferentiabilityContinuityAnalyseassertion_reasoneasy
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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.