1. Chapter 11 Class 12 Three Dimensional Geometry
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Example, 2 - Chapter 11 Class 12 Three Dimensional Geometry

Last updated at Dec. 16, 2024 by Teachoo

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Example 2 If a line has direction ratios 2, โ€“ 1, โ€“ 2, determine its direction cosines.If direction ratios of a line are a, b, c direction cosines are ๐’‚/โˆš(๐’‚^๐Ÿ + ๐’ƒ^๐Ÿ + ๐’„^๐Ÿ ) , ๐’ƒ/โˆš(๐’‚^๐Ÿ + ๐’ƒ^๐Ÿ + ๐’„^๐Ÿ ) , ๐’„/โˆš(๐’‚^๐Ÿ + ๐’ƒ^๐Ÿ + ๐’„^๐Ÿ ) Given, Direction ratios = 2, โˆ’1, โˆ’2 โˆด ๐‘Ž = 2, b = โˆ’1, c = โˆ’2 Also, โˆš(๐’‚^๐Ÿ + ๐’ƒ^๐Ÿ + ๐’„^๐Ÿ ) = โˆš(22 + (โˆ’1)2 + (โˆ’2)2) = โˆš(4 + 1 + 4) = โˆš9 = 3 Direction cosines = ๐‘Ž/โˆš(๐‘Ž^2 + ๐‘^2 + ๐‘^2 ) , ๐‘/โˆš(๐‘Ž^2 + ๐‘^2 + ๐‘^2 ) , ๐‘/โˆš(๐‘Ž^2 + ๐‘^2 + ๐‘^2 ) = ๐Ÿ/๐Ÿ‘ , (โˆ’๐Ÿ)/๐Ÿ‘ , (โˆ’๐Ÿ)/๐Ÿ‘
  1. Chapter 11 Class 12 Three Dimensional Geometry
  2. Serial order wise

    3. Examples

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Chapter 11 Class 12 Three Dimensional Geometry
Serial order wise

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Davneet Singh

Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 14 years. He provides courses for Maths, Science and Computer Science at Teachoo