Ex 10.5, 1 (Supplementary NCERT) - Find [a b c] if a = i - 2j + 3k

Ex 10.5, 1 (Supplementary NCERT) - Chapter 10 Class 12 Vector Algebra - Part 2

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

Transcript

Ex 10.5, 1 (Supplementary NCERT) Find [π‘Ž βƒ—" " 𝑏 βƒ—" " 𝑐 βƒ— ] if π‘Ž βƒ— = 𝑖 Μ‚ – 2𝑗 Μ‚ + 3π‘˜ Μ‚ , 𝑏 βƒ— = 2𝑖 Μ‚ – 3𝑗 Μ‚ + π‘˜ Μ‚ , 𝑐 βƒ— = 3𝑖 Μ‚ + 𝑗 Μ‚ – 2π‘˜ Μ‚Given, 𝒂 βƒ— = 𝑖 Μ‚ – 2𝑗 Μ‚ + 3π‘˜ Μ‚ , 𝒃 βƒ— = 2𝑖 Μ‚ – 3𝑗 Μ‚ + π‘˜ Μ‚ , 𝒄 βƒ— = 3𝑖 Μ‚ + 𝑗 Μ‚ – 2π‘˜ Μ‚ Now, 𝒂 βƒ—.(𝒃 βƒ— Γ— 𝒄 βƒ—) = [π‘Ž βƒ—" " 𝑏 βƒ—" " 𝑐 βƒ— ] = |β– 8(𝟏&βˆ’πŸ&πŸ‘@𝟐&βˆ’πŸ‘&𝟏@πŸ‘&𝟏&βˆ’πŸ)| = 1[(βˆ’3Γ—βˆ’2)βˆ’(1Γ—1) ] βˆ’ (–2)[(2Γ—βˆ’2)βˆ’(3Γ—1) ] + 3[(2Γ—1)βˆ’(3Γ—βˆ’3)] = 1 [6βˆ’1]+2(βˆ’4βˆ’3)+3[2+9] = 1(5) + 2(–7) + 3(11) = 5 – 14 + 33 = 38 – 14 = 24 ∴ [π‘Ž βƒ—" " 𝑏 βƒ—" " 𝑐 βƒ— ] = 24

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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.