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If → a , → B , → C Are Three Unit Vectors Such that → a × → B = → C , → B × → C = → a , → C × → a = → B . Show that → a , → B , → C Form an Orthonormal Right Handed Triad of Unit Vectors. - Mathematics

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प्रश्न

If \[\vec{a,} \vec{b,} \vec{c}\] are three unit vectors such that \[\vec{a} \times \vec{b} = \vec{c} , \vec{b} \times \vec{c} = \vec{a,} \vec{c} \times \vec{a} = \vec{b} .\]  Show that \[\vec{a,} \vec{b,} \vec{c}\] form an orthonormal right handed triad of unit vectors.

 
 
 

 

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उत्तर

\[\text{ Given } :\]
\[ \vec{a} \times \vec{b} = \vec{c} \]
\[ \vec{b} \times \vec{c} = \vec{a} \]
\[ \vec{c} \times \vec{a} = \vec{b} . . . (1)\]
\[\text{ Now } ,\]
\[\left| \vec{a} \times \vec{b} \right| = \left| \vec{c} \right| = 1 (\because \vec{c} \text{ is a unit vector } )\]
\[\left| \vec{b} \times \vec{c} \right| = \left| \vec{a} \right| = 1 (\because \vec{a} \text{ is a unit vector } )\]
\[\left| \vec{c} \times \vec{a} \right| = \left| \vec{b} \right| = 1 (\because \vec{b} \text{ is a unit vector } )\]
\[ \therefore \left| \vec{a} \times \vec{b} \right| = \left| \vec{b} \times \vec{c} \right| = \left| \vec{c} \times \vec{a} \right| = 1 . . . (2)\]
\[ \text{ From (1) and (2), we know } \]
\[ \vec{a} , \vec{b} \text{ and }  \vec{c} \text{ form an orthonormal right handed triad of unit vectors. } \]

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अध्याय 25: Vector or Cross Product - Exercise 25.1 [पृष्ठ ३०]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 25 Vector or Cross Product
Exercise 25.1 | Q 18 | पृष्ठ ३०

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