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If the Vectors → a and → B Are Such that | → a | = 3 , ∣ ∣ → B ∣ ∣ = 2 3 and → a × → B is a Unit Vector, Then Write the Angle Between → a and → B - Mathematics

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प्रश्न

If the vectors \[\vec{a}\]  and \[\vec{b}\] are such that \[\left| \vec{a} \right| = 3, \left| \vec{b} \right| = \frac{2}{3}\] and \[\vec{a} \times \vec{b}\] is a unit vector, then write the angle between \[\vec{a}\] and \[\vec{b}\] 

उत्तर

Let the angle between \[\vec{a}\] and \[\vec{b}\]  be \[\theta\] It is given that \[\vec{a} \times \vec{b}\]  is a unit vector. 

\[\therefore \left| \vec{a} \times \vec{b} \right| = 1\]
\[ \Rightarrow \left| \vec{a} \right|\left| \vec{b} \right|\sin\theta = 1\]
\[ \Rightarrow 3 \times \frac{2}{3} \times \sin\theta = 1\]
\[ \Rightarrow \sin\theta = \frac{1}{2}\]
\[ \Rightarrow \theta = \frac{\pi}{6}\] 

Thus, the angle between \[\vec{a}\] and \[\vec{b}\] is \[\frac{\pi}{6}\] 

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अध्याय 24: Scalar Or Dot Product - very short answer [पृष्ठ ४८]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 24 Scalar Or Dot Product
very short answer | Q 40 | पृष्ठ ४८

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