The magnitude of projection of  (2i − j + k ) on (i − 2j + 2k ) is _______

The magnitude of projection of  (2i − j + k ) on (i − 2j + 2k ) is ___

Question 15 (OR 1st Question) - CBSE Class 12 Sample Paper for 2020 Boards - Part 2


Transcript

Question 15 (OR 1st Question) The magnitude of projection of (2๐‘– ฬ‚ โˆ’ ๐‘— ฬ‚ + ๐‘˜ ฬ‚) on (๐‘– ฬ‚ โˆ’ 2๐‘— ฬ‚ + 2๐‘˜ ฬ‚) is _______ Projection of vector ๐’‚ โƒ— on ๐’ƒ โƒ— = ๐Ÿ/|๐’ƒ โƒ— | (๐’‚ โƒ—. ๐’ƒ โƒ—) Let ๐‘Ž โƒ— = 2๐‘– ฬ‚ โ€“ ๐‘— ฬ‚ + ๐‘˜ ฬ‚ ๐‘ โƒ— = ๐‘– ฬ‚ โ€“ 2๐‘— ฬ‚ + 2๐‘˜ ฬ‚ (๐’‚ โƒ— . ๐’ƒ โƒ—) = (2 ร— 1) + (โ€“1 ร— โˆ’2) + (1 ร— 2) = 2 + 2 + 2 = 6 Magnitude of ๐‘ โƒ— = โˆš(12+(โˆ’2)2+22) |๐‘ โƒ— | = โˆš(1+4+4) |๐‘ โƒ— | = โˆš9 |๐‘ โƒ— | = 3 Projection of ๐‘Ž โƒ— on ๐‘ โƒ— = 1/|๐‘ โƒ— | (๐‘Ž โƒ—. ๐‘ โƒ—) = 1/3 ร— 6 = 2 โˆด Magnitude of projection is 2 units

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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.