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Find the Value of θ ∈(0, π/2) for Which Vectors → a = ( Sin θ ) ^ I + ( Cos θ ) ^ J and → B = ^ I − √ 3 ^ J + 2 ^ K Are Perpendicular. - Mathematics

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प्रश्न

Find the value of θ ∈(0, π/2) for which vectors \[\vec{a} = \left( \sin \theta \right) \hat{i} + \left( \cos \theta \right) \hat{j} \text{ and } \vec{b} = \hat{i} - \sqrt{3} \hat{j} + 2 \hat{k}\] are perpendicular.

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उत्तर

\[\text{ We have }\]

\[ \vec{a} = \left( \sin \theta \right) \hat{i} + \left( \cos \theta \right) \hat{j} \]

\[\text{ and }\]

\[ \vec{b} = \hat{i} - \sqrt{3} \hat{j} + 2 \hat{k} \]

\[\text{ It is given that the vectors are perpendicular }.\]

\[ \Rightarrow \vec{a} . \vec{b} = 0\]

\[ \Rightarrow \sin \theta - \sqrt{3} \cos \theta = 0\]

\[ \Rightarrow \sin \theta = \sqrt{3} \cos \theta\]

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

\[ \Rightarrow \theta = \frac{\pi}{3}\]

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अध्याय 24: Scalar Or Dot Product - very short answer [पृष्ठ ४७]

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आरडी शर्मा Mathematics [English] Class 12
अध्याय 24 Scalar Or Dot Product
very short answer | Q 20 | पृष्ठ ४७

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