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Misc 5 - Find x for which x(i + j + k) is a unit vector.

Misc 5 - Chapter 10 Class 12 Vector Algebra - Part 2

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Misc 5 Find the value of x for which x(𝑖 ̂ + 𝑗 ̂ + 𝑘 ̂) is a unit vector.Let 𝑎 ⃗ = x(𝑖 ̂ + 𝑗 ̂ + 𝑘 ̂) So, 𝑎 ⃗ = 𝑥𝑖 ̂ + 𝑥𝑗 ̂ + 𝑥𝑘 ̂ Given, 𝑎 ⃗ is a unit vector Magnitude of 𝑎 ⃗ is 1. So, |𝒂 ⃗ | = 1 Thus, Magnitude of 𝒂 ⃗ = 1 √(𝑥^2+𝑥2+𝑥2) = 1 √3𝑥2 = 1 ±√3 𝑥 = 1 𝒙 = ±𝟏/√𝟑 Note We take ± because x can have both positive and negative value

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Davneet Singh has done his B.Tech from Indian Institute of Technology, Kanpur. He has been teaching from the past 13 years. He provides courses for Maths, Science, Social Science, Physics, Chemistry, Computer Science at Teachoo.