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Write the Value of ( ^ I × ^ J ) ⋅ ^ K + ( ^ J + ^ K ) ⋅ ^ J - Mathematics

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प्रश्न

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

 
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उत्तर

\[\left( \hat{ i }  \times \hat{ j }  \right) . \hat{ k }  + \left( \hat{ j }  + \hat{ k }  \right) . \hat{ j }  \]
\[ = \hat{ k } . \hat{ k }  + \hat{  j }  . \hat{ j }  + \hat{ k }  . \hat{ j }  ( \because \hat{ i }  \times \hat{ j } = \hat{ k }  ) \]
\[ = \left| \hat{ k }  \right|^2 + \left| \hat{ j }  \right|^2 + 0 ( \because \hat{ k }  . \hat{ j }  = 0)\]
\[ = 1^2 + 1^2 \]
\[ = 2\]

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अध्याय 25: Vector or Cross Product - very short answers [पृष्ठ ३४]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 25 Vector or Cross Product
very short answers | Q 28 | पृष्ठ ३४

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