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What Are the Direction Cosines of X-axis?

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Question

What are the direction cosines of X-axis?

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Solution

\[\text { The x - axis makes angles 0°, 90° and 90° with x, y and z axes, respectively } . \]

\[\text{ Therefore, the direction cosines of x - axis are  cos 0°, cos 90° , cos 90° , i . e}  . 1, 0, 0 .\]

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Chapter 26: Direction Cosines and Direction Ratios - Very Short Answers [Page 24]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 26 Direction Cosines and Direction Ratios
Very Short Answers | Q 2 | Page 24

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