CBSE 2026 · Region 2 · Set 1 · Q20 · 1 mark
Assertion (A) : A line can have direction cosines < $\displaystyle 1$, $\displaystyle 1$, $\displaystyle 1$ >
Reason (R) : $\displaystyle \cos \theta=1$ is possible for $\displaystyle \theta=0$.
Official answer
From CBSE’s own marking scheme for this paper.
(D)
Assertion (A) is false, but Reason (R) is true.
Three Dimensional GeometryDirection Cosines and Direction Ratios of a LineUnderstandassertion_reasonmedium
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CBSE Class 12 Mathematics past-paper question from the 2026board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.