Question 4 - CBSE Class 12 Sample Paper for 2022 Boards (For Term 2) - Solutions of Sample Papers and Past Year Papers - for Class 12 Boards

Last updated at April 16, 2024 by

Find the direction cosines of the following line: (3 − 𝑥)/(−1) = (2𝑦 − 1)/2 = 𝑧/4

This question is similar to Question 4 or 2nd CBSE Class 12 Sample Paper 2019 Boards 

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Question 4 Find the direction cosines of the following line: (3 − 𝑥)/(−1) = (2𝑦 − 1)/2 = 𝑧/4 Given line (𝟑 − 𝒙)/(−𝟏) = (2𝑦 − 1)/2 = 𝑧/4 (−(𝑥 − 3) )/(−1) = (2𝑦 − 1)/2 = 𝑧/4 ((𝒙 − 𝟑) )/𝟏 = (2𝑦 − 1)/2 = 𝑧/4 ((𝑥 − 3) )/1 = 𝟐(𝒚 − ½)/𝟐 = 𝑧/4 ((𝑥 − 3) )/1 = ((𝒚 − ½))/𝟏 = 𝑧/4 So, direction ratios are 1, 1, 4 ½ marks ∴ a = 1, b = 1, c = 4 Direction cosines = 1/√(1^2 + 1^2 + 4^2 ) , 1/√(1^2 + 1^2 + 4^2 ) , 4/√(1^2 + 1^2 + 4^2 ) = 1/√(1 + 1 + 16) ,1/√(1 + 1 + 16) ,4/√(1 + 1 + 16) = 1/√18 ,1/√18 ,4/√18 = 1/√(2 × 9) ,1/√(2 × 9) ,4/√(2 × 9) = 𝟏/(𝟑√𝟐) , 𝟏/(𝟑√𝟐) , 𝟒/(𝟑√𝟐) ½ marks

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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, Social Science, Physics, Chemistry, Computer Science at Teachoo.