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For any three vectors → a , → b and → c write the value of → a × ( → b + → c ) + → b × ( → c + → a ) + → c × ( → a + → b ) . - Mathematics

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प्रश्न

For any three vectors \[\vec{a,} \vec{b} \text{ and }  \vec{c}\] write the value of \[\vec{a} \times \left( \vec{b} + \vec{c} \right) + \vec{b} \times \left( \vec{c} + \vec{a} \right) + \vec{c} \times \left( \vec{a} + \vec{b} \right) .\]

 
 
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उत्तर

\[\vec{a} \times \left( \vec{b} + \vec{c} \right) + \vec{b} \times \left( \vec{c} + \vec{a} \right) + \vec{c} \times \left( \vec{a} + \vec{b} \right)\]
\[ = \left( \vec{a} \times \vec{b} \right) + \left( \vec{a} \times \vec{c} \right) + \left( \vec{b} \times \vec{c} \right) + \left( \vec{b} \times \vec{a} \right) + \left( \vec{c} \times \vec{a} \right) + \left( \vec{c} \times \vec{b} \right)\]
\[ = \left( \vec{a} \times \vec{b} \right) + \left( \vec{a} \times \vec{c} \right) + \left( \vec{b} \times \vec{c} \right) - \left( \vec{a} \times \vec{b} \right) - \left( \vec{a} \times \vec{c} \right) - \left( \vec{b} \times \vec{c} \right)\]
\[ = \vec{0}\]

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अध्याय 25: Vector or Cross Product - very short answers [पृष्ठ ३३]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 25 Vector or Cross Product
very short answers | Q 12 | पृष्ठ ३३

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