Last updated at Feb. 1, 2020 by Teachoo

Transcript

Misc 4 (Introduction) Find the equation of a line parallel to x-axis and passing through the origin.Direction cosines of a line making angle ๐ผ with x -axis, ๐ฝ with y โ axis and ๐พ with z โ axis are l, m, n l = cos ๐ผ , m = cos ๐ฝ , n = cos ๐พ x โ axis makes an angle 0ยฐ with x โ axis, 90ยฐ with y โ axis & 90ยฐ with z โ axis. So, ๐ผ = 0ยฐ, ๐ฝ = 90ยฐ, ๐พ = 90ยฐ Direction cosines are l = cos 0ยฐ , m = cos 90ยฐ , n = cos 90ยฐ l = 1 , m = 0, n = 0 โด Direction cosines of x โ axis are 1, 0, 0. Misc 4 Find the equation of a line parallel to x-axis and passing through the origin.Equation of a line passing through (x1, y1, z1) and parallel to a line with direction ratios a, b, c is (๐ โ ๐๐)/๐ = (๐ โ ๐๐)/๐ = (๐ โ ๐๐)/๐ Since line passes through origin ie. (0, 0, 0), x1 = 0, y1 = 0, z1 = 0 Since line is parallel to x โ axis, ๐ = 1, b = 0, c = 0 Equation of line is (๐ฅ โ 0)/1 = (๐ฆ โ 0)/0 = (๐ง โ 0)/0 ๐/๐ = ๐/๐ = ๐/๐

Miscellaneous

Misc 1
Important

Misc 2

Misc 3 Deleted for CBSE Board 2021 Exams only

Misc 4 Important You are here

Misc 5 Important Deleted for CBSE Board 2021 Exams only

Misc 6 Important

Misc 7

Misc 8 Important

Misc 9 Important

Misc 10

Misc 11 Important

Misc 12 Important

Misc 13 Important

Misc 14 Important

Misc 15 Important

Misc 16 Important

Misc 17 Important

Misc 18 Important

Misc 19 Important

Misc 20 Important

Misc 21 Important

Misc 22 Important

Misc 23 Important

Chapter 11 Class 12 Three Dimensional Geometry

Serial order wise

About the Author

Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 10 years. He provides courses for Maths and Science at Teachoo.