Last updated at Jan. 3, 2020 by Teachoo
Transcript
Example, 3 Find the direction cosines of the line passing through the two points ( 2, 4, 5) and (1, 2, 3). P ( 2, 4, 5) Q (1, 2, 3) So, x1 = 2, y1 = 4 , z1 = 5 & x2 = 1, y2 = 2 , z2 = 3 Direction ratios = (x2 x1), (y2 y1), (z2 z1) = 1 ( 2) , 2 4 , 3 ( 5) = 1 + 2, 2, 3 + 5 = 3, 2, 8 Direction cosines = 3 32 + 2 2 + 82 , 2 32 + 2 2 + 82 , 8 32 + 2 2 + 82 = 3 9 + 4 + 64 , 2 9 + 4 + 64 , 8 9 + 4 + 64 = , ,
Chapter 11 Class 12 Three Dimensional Geometry
Ex 11.1, 2
Example, 6 Important
Example, 9 Deleted for CBSE Board 2021 Exams only
Example 12 Important
Ex 11.2, 5 Important
Ex 11.2, 11 Important Deleted for CBSE Board 2021 Exams only
Ex 11.2, 12 Important
Ex 11.2, 14 Important
Ex 11.2, 15 Important
Ex 11.2, 17 Important
Example 20 Important
Example 21 Important
Example 23 Important Deleted for CBSE Board 2021 Exams only
Example 24
Example, 25 Important
Ex 11.3, 4 Important
Ex 11.3, 11 Important
Ex 11.3, 12 Important Deleted for CBSE Board 2021 Exams only
Ex 11.3, 14 (a) Important
Example 27 Important
Example 29 Important
Example 30 Important
Misc 6 Important
Misc 9 Important
Misc 14 Important
Misc 18 Important
Misc 20 Important
Misc 21 Important
Chapter 11 Class 12 Three Dimensional Geometry
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