Same chapter3 marksDifficulty: Medium
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3 marksDifficulty: Medium
Define direction cosines and state the relation they satisfy.
Original Khojo Papers practice question — not from a past board paper.
Answer
The direction cosines of a line are the cosines of the angles it makes with the positive directions of the three coordinate axes, usually written l, m and n. They satisfy l2 + m2 + n2 = 1.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Direction ratios are any numbers proportional to the direction cosines.
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