Ex 10.2, 12 - Find direction cosines of i + 2j + 3k - Direction cosines and ratios

  1. Chapter 10 Class 12 Vector Algebra
  2. Serial order wise

Transcript

Ex 10.2, 12 Find the direction cosines of the vector 𝑖﷯ + 2 𝑗﷯ + 3 𝑘﷯ . Let 𝑎﷯ = 𝑖﷯ + 2 𝑗﷯ + 3 𝑘﷯ = 1 𝑖﷯ + 2 𝑗﷯ + 3 𝑘﷯ Direction ratios are a = 1 , b = 2 , c = 3 Magnitude of 𝑎﷯ = ﷮12+ 2﷮2﷯+ 3﷮2﷯﷯ 𝑎﷯﷯ = ﷮1+4+9﷯ = ﷮14﷯ Direction cosines are 𝑎﷮ 𝑎﷯﷯﷯, 𝑏﷮ 𝑎﷯﷯﷯, 𝑐﷮ 𝑎﷯﷯﷯﷯ Direction cosines of 𝑎﷯ = 𝟏﷮ ﷮𝟏𝟒﷯﷯, 𝟐﷮ ﷮𝟏𝟒﷯﷯, 𝟑﷮ ﷮𝟏𝟒﷯﷯﷯

About the Author

Davneet Singh's photo - Teacher, Computer Engineer, Marketer
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 8 years. He provides courses for Maths and Science at Teachoo. You can check his NCERT Solutions from Class 6 to 12.