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If → a and → B Are Two Vectors Such that ∣ ∣ → a × → B ∣ ∣ = √ 3 and → a . → B = 1 , Find the Angle Between. - Mathematics

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प्रश्न

If   \[\vec{a} \text{ and }  \vec{b}\] are two vectors such that \[\left| \vec{a} \times \vec{b} \right| = \sqrt{3}\text{ and }  \vec{a} . \vec{b} = 1,\]  find the angle between.

 
 

 

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उत्तर

\[\left| \vec{a} \times \vec{b} \right| = \sqrt{3}\]

\[ \Rightarrow \left| \vec{a} \right| \left| \vec{b} \right| \sin \theta = \sqrt{3} . . . (1)\]

\[ \vec{a} . \vec{b} = 1\]

\[ \Rightarrow \left| \vec{a} \right| \left| \vec{b} \right| \cos \theta = 1 . . . (2)\]

\[\text{ Dividing (1) by (2), we get } \]

\[\frac{\left| \vec{a} \right| \left| \vec{b} \right| \sin \theta}{\left| \vec{a} \right| \left| \vec{b} \right| \cos \theta} = \sqrt{3}\]

\[ \Rightarrow \tan \theta = \sqrt{3}\]

\[ \Rightarrow \theta = {60}^o \]

 

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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 11 | पृष्ठ ३३

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