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The value of ^ i ⋅ ( ^ j × ^ k ) + ^ j ⋅ ( ^ i × ^ k ) + ^ k ⋅ ( ^ i × ^ j ) , is - Mathematics

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प्रश्न

The value of  \[\hat{ i }  \cdot \left( \hat{ j }  \times \hat{ k }  \right) + \hat{ j }  \cdot \left( \hat{ i }  \times \hat{ k }  \right) + \hat{ k }  \cdot \left( \hat{ i }  \times \hat{ j }  \right),\]  is 

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MCQ

उत्तर

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

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अध्याय 25: Vector or Cross Product - MCQ [पृष्ठ ३६]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 25 Vector or Cross Product
MCQ | Q 14 | पृष्ठ ३६

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