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The value of λ for which the two vectors 2i^-j^+2k^ and λ3i^+λj^+k^ are perpendicular is ______. - Mathematics

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Question

The value of λ for which the two vectors `2hati - hatj + 2hatk` and `3hati + λhatj + hatk` are perpendicular is ______.

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  • 2

  • 4

  • 6

  • 8

MCQ
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Solution

The value of λ for which the two vectors `2hati - hatj + 2hatk` and `3hati + lambdahatj + hatk` are perpendicular is 8.

Explanation:

Dot product of two mutually perpendicular vectors is zero.

`\implies` 2 × 3 + (–1)λ + 2 × 1 = 0

`\implies` λ = 8.

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Chapter 10: Vector Algebra - Solved Examples [Page 212]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 10 Vector Algebra
Solved Examples | Q 14 | Page 212

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