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If → c is a unit vector perpendicular to the vectors → a and → b , write another unit vector perpendicular to → a and → b . - Mathematics

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Question

If  \[\vec{c}\] is a unit vector perpendicular to the vectors \[\vec{a} \text{ and } \vec{b} ,\]  write another unit vector perpendicular to \[\vec{a} \text{ and }  \vec{b} .\]

 
 

 

Short Note

Solution

\[\vec{c} \text{ is a unit vector perpendicular to both } \vec{a} \text{ and }  \vec{b} .\]

\[\Rightarrow \vec{c} =\frac{\vec{a} \times \vec{b}}{\left| \vec{a} \times \vec{b} \right|}\]

\[\Rightarrow- \vec{c} =\frac{\vec{b} \times \vec{a}}{\left| \vec{a} \times \vec{b} \right|}\]

\[\text{ Therefore,}  - \vec{c} \text{ is perpendicular to }  \vec{b} \text{ and }  \vec{a .} \]

\[\text{ Thus } , - \vec{c} \text{ is another unit vector perpendicular to }  \vec{a} \text{ and } \vec{b .}\]

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Chapter 25: Vector or Cross Product - very short answers [Page 34]

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RD Sharma Mathematics [English] Class 12
Chapter 25 Vector or Cross Product
very short answers | Q 23 | Page 34

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