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CBSE Class 12 Mathematics 2026 Main Paper 65/2/1 · Q201 Marksdirection_cosines

CBSE Class 12 Mathematics 2026 Main Paper 65/2/1 · Question 20 (Three Dimensional Geometry)

Assertion: A line can have direction cosines (1,1,1). Reason: cos θ=1 is possible for θ=0.

✅ Step-by-Step Solution

Final Answer: The assertion is false and the reason is true.
  1. The squares of a line’s direction cosines must sum to one, but here they sum to three. The stated cosine value is true.

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All Questions in CBSE Class 12 Mathematics 2026 Main Paper 65/2/1

Q1Q2Q3Q4Q5Q6Q7Q8Q9Q10Q11Q12Q13Q14Q15Q16Q17Q18Q19Q20Q21Q22Q23Q24Q25Q26Q27Q28Q29Q30Q31Q32Q33Q34Q35Q36Q37Q38

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