मराठी

If the Direction Ratios of a Line Are Proportional to 1, −3, 2, Then Its Direction Cosines Are (A) 1 √ 14 , − 3 √ 14 , 2 √ 14 (B) 1 √ 14 , 2 √ 14 , 3 √ 14 (C) − 1 √ 14 , 3 √ 14 , 2 √ 14

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प्रश्न

If the direction ratios of a line are proportional to 1, −3, 2, then its direction cosines are

 

पर्याय

  •  \[\frac{1}{\sqrt{14}}, - \frac{3}{\sqrt{14}}, \frac{2}{\sqrt{14}}\] 

  •  \[\frac{1}{\sqrt{14}}, \frac{2}{\sqrt{14}}, \frac{3}{\sqrt{14}}\] 

  •  \[- \frac{1}{\sqrt{14}}, \frac{3}{\sqrt{14}}, \frac{2}{\sqrt{14}}\] 

  •  \[- \frac{1}{\sqrt{14}}, - \frac{2}{\sqrt{14}}, - \frac{3}{\sqrt{14}}\]

MCQ
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उत्तर

 \[\frac{1}{\sqrt{14}}, - \frac{3}{\sqrt{14}}, \frac{2}{\sqrt{14}}\] 

The direction ratios of the line are proportional to 1, -3, 2 .

∴  The direction cosines of the line are

\[\frac{1}{\sqrt{1^2 + \left( - 3 \right)^2 + 2^2}}, \frac{- 3}{\sqrt{1^2 + \left( - 3 \right)^2 + 2^2}}, \frac{2}{\sqrt{1^2 + \left( - 3 \right)^2 + 2^2}} \]

\[ = \frac{1}{\sqrt{14}}, \frac{- 3}{\sqrt{14}}, \frac{2}{\sqrt{14}}\]

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पाठ 27: Straight Line in Space - MCQ [पृष्ठ ४३]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
पाठ 27 Straight Line in Space
MCQ | Q 9 | पृष्ठ ४३

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