Same chapter3 marksDifficulty: Medium
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3 marksDifficulty: Medium
Find the angle between the line with direction ratios 1, 1, 2 and the plane x + y + z = 5.
Original Khojo Papers practice question — not from a past board paper.
Answer
sin−1(4/√18), about 70.5°
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The angle between a line and a plane is sin−1 of the modulus of the cosine of the angle between the line and the normal: sin θ = |1 + 1 + 2| ÷ (√6 × √3) = 4/√18.
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