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Write the value of ^ i . ( ^ j × ^ k ) + ^ j . ( ^ k × ^ i ) + ^ k . ( ^ i × ^ j ) . - Mathematics

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Question

Write the value of  \[\hat{ i } . \left( \hat{ j } \times \hat{ k }  \right) + \hat{ j }  . \left( \hat{ k } \times \hat{ i }  \right) + \hat{ k }  . \left( \hat{ i }  \times \hat{ j }  \right) .\]

 

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Solution

\[\hat{ i } . \left( \hat{ j } \times \hat{ k } \right) + \hat{ j } . \left( \hat{ k } \times \hat{ i }  \right) + \hat{ k }  . \left( \hat{ i }  \times \hat{ j } \right)\]
\[ = \hat{ i }  . \hat{ i}  + \hat{ j} . j + \hat{ k }  . \hat{ k } \]
\[ = \left| \hat{ i } \right|^2 + \left| \hat{ j }  \right|^2 + \left| \hat{ k }  \right|^2 \]
= 1 + 1 - 1

= 3 

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Chapter 25: Vector or Cross Product - very short answers [Page 33]

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RD Sharma Mathematics [English] Class 12
Chapter 25 Vector or Cross Product
very short answers | Q 4 | Page 33

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