Same chapter3 marksDifficulty: Medium
Find the equation of the plane passing through (1, 2, 3) with normal vector 2i − j + 3k.
Three-Dimensional Geometry
3 marksDifficulty: Medium
Find the angle between the planes 2x + y − 2z = 5 and 3x − 6y − 2z = 7.
Original Khojo Papers practice question — not from a past board paper.
Answer
cos−1(4/21), about 79°
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The angle between two planes is the angle between their normals, so cos θ = (6 − 6 + 4) ÷ (3 × 7) = 4/21.
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