Ex 10.2, 11 - Chapter 10 Class 12 Vector Algebra
Last updated at May 29, 2018 by Teachoo
Transcript
Ex 10.2, 11 Show that the vectors 2 𝑖 − 3 𝑗 + 4 𝑘 and − 4 𝑖 + 6 𝑗 − 8 𝑘 are collinear. Magnitude of 𝑎 = 22+ −32+42 𝑎 = 4+9+16 = 29 Directions cosines of 𝑎 = 2 29, −3 29, 4 29 Hence, Direction cosines of 𝒂 = (−1) × Direction cosines of 𝒃 ∴ They have opposite directions Since 𝑎 and 𝑏 are parallel to the same line 𝑚, they are collinear. Hence proved
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