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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 \[\hat{ i }  × \left( \hat{ j } + \hat{ k }  \right) + \hat{ j }   ×  \left( \hat{ k } + \hat{ i }  \right) + \hat{ k }  ×   \left( \hat{ i }  + \hat{ j }  \right) .\]

 
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Solution

\[\hat{ i }  \times \left( \hat{ j } + \hat{ k } \right) + \hat{ j }  \times \left( \hat{ k }  + \hat{ i }  \right) + \hat{ k }  \times \left( \hat{ i }  + \hat{ j }  \right)\]
\[ = \left( \hat{ i } \times \hat{ j } \right) + \left( \hat{ i }  \times \hat{ k }  \right) + \left( \hat{ j }  \times \hat{ k }  \right) + \left( \hat{ j }  \times \hat{ i}  \right) + \left( \hat{ k } \times \hat{ i }  \right) + \left( \hat{ k }  \times \hat{ j }  \right)\]
\[ = \hat{ k }  - \hat{ j }  + \hat{ i }  - \hat{ k }  + \hat{ j }  - \hat{ i }  \]
\[ = \vec{0}\] 

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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 5 | Page 33

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