Supplementary examples and questions from CBSE
Supplementary Example 2 Important
Supplementary Example 3 You are here
Supplementary Example 4
Supplementary Example 5 Important
Supplementary Example 6
Supplementary Exercise Q1
Supplementary Exercise Q2
Supplementary Exercise Q3
Supplementary Exercise Q4 Important
Supplementary Exercise Q5
Supplementary Exercise Q6 Important
Supplementary Exercise Q7
Supplementary Exercise Q8
Supplementary Exercise Q9 Important
Supplementary Exercise Q10
Supplementary examples and questions from CBSE
Last updated at Dec. 16, 2024 by Teachoo
Supplementary Example 3 Show that the vectors 𝑎 ⃗ = −4𝑖 ̂ − 6𝑗 ̂ − 2𝑘 ̂, 𝑏 ⃗ = −𝑖 ̂ + 4𝑗 ̂ + 3𝑘 ̂ and 𝑐 ⃗ = −8𝑖 ̂ − 𝑗 ̂ + 3𝑘 ̂ are coplanar Three vectors 𝑎 ⃗, 𝑏 ⃗, 𝑐 ⃗ are coplanar if [𝒂 ⃗" " 𝒃 ⃗" " 𝒄 ⃗ ] = 0 Given, 𝑎 ⃗ = –4𝑖 ̂ − 6𝑗 ̂ – 2𝑘 ̂ 𝑏 ⃗ = −𝑖 ̂ + 4𝑗 ̂ + 3𝑘 ̂ 𝑐 ⃗ = –8𝑖 ̂ − 𝑗 ̂ + 3𝑘 ̂ [𝑎 ⃗" " 𝑏 ⃗" " 𝑐 ⃗ ] = |■8(−4&−6&−2@−1&4&3@−8&−1&3)| = –4[(4×3)−(−1×3) ] − (−6) [(−1×3)−(−8×3) ] + (–2)[(−1×−1)−(−8×4)] = –4 [12+3]+6(−3+24)−2[1+32] = –4(15) + 6 (21) –2(33) = –60 + 126 – 66 = 0 Since [𝑎 ⃗" " 𝑏 ⃗" " 𝑐 ⃗ ] = 0 Vectors 𝑎 ⃗, 𝑏 ⃗, 𝑐 ⃗ are coplanar