Example 5 - Let a = i + 2j, b = 2i + j. Is |a| = |b|? - Examples

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

Learn in your speed, with individual attention - Teachoo Maths 1-on-1 Class


Transcript

Example 5 Let 𝑎 ⃗ = 𝑖 ̂ + 2𝑗 ̂ and 𝑏 ⃗ = 2𝑖 ̂ + 𝑗 ̂ . Is |𝑎 ⃗ | = |𝑏 ⃗ | ? Are the vectors 𝑎 ⃗ and 𝑏 ⃗ equal? Given 𝒂 ⃗ = 𝑖 ̂ + 2𝑗 ̂ & 𝒃 ⃗ = 2𝑖 ̂ + 𝑗 ̂ So, we can we can write, 𝒂 ⃗ = 1𝑖 ̂ + 2𝑗 ̂ + 0𝑘 ̂ & 𝒃 ⃗ = 2𝑖 ̂ + 1𝑗 ̂ + 0𝑘 ̂ Magnitude of 𝒂 ⃗ |𝑎 ⃗ | = √(12+22+02) = √5 Magnitude of 𝒃 ⃗ |𝑏 ⃗ | = √(22+12+02) = √5 Therefore, |𝒂 ⃗ | = |𝒃 ⃗ | Checking if 𝒂 ⃗ and 𝒃 ⃗ are equal 𝑎 ⃗ = 1𝑖 ̂ + 2𝑗 ̂ + 0𝑘 ̂ & 𝑏 ⃗ = 2𝑖 ̂ + 1𝑗 ̂ + 0𝑘 ̂ Comparing corresponding components, As 1 ≠ 2 Thus, 𝑎 ⃗ and 𝑏 ⃗ are not equal since their corresponding components are distinct.

Ask a doubt
Davneet Singh's photo - Co-founder, Teachoo

Made by

Davneet Singh

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.