हिंदी

The Adjacent Sides of a Parallelogram Are Represented by the Vectors → a = ^ I + ^ J − ^ K and → B = − 2 ^ I + ^ J + 2 ^ K . Find Unit Vectors Parallel to the Diagonals of the Parallelogram.

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प्रश्न

The adjacent sides of a parallelogram are represented by the vectors \[\vec{a} = \hat{i} + \hat{j} - \hat{k}\text{ and }\vec{b} = - 2 \hat{i} + \hat{j} + 2 \hat{k} .\]
Find unit vectors parallel to the diagonals of the parallelogram.

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उत्तर


\[\vec{a} = \hat{i} + \hat{j} - \hat{k} \text{ and }\vec{b} = - 2 \hat{i} + \hat{j} + 2 \hat{k} .\]
\[\overrightarrow{AC} = \vec{a} + \vec{b}  = - \hat{i} + 2 \hat{j} + \hat{k}\]

\[\text{Let the unit vector along the diagonals AC and BD of the parallelogram be }\widehat{AC}\text{ and }\widehat{BD} . \]

\[ \Rightarrow  \widehat{AC} = \frac{- \hat{i} + 2 \hat{j} + \hat{k}}{\sqrt{6}}\]

\[\text{ Similarly, } \overrightarrow{BD} =  \vec{b} - \vec{a} =  - 3\hat{i} + 3 \hat{k} \]
\[\Rightarrow \widehat{BD} = \frac{- 3 \hat{i} + 3 \hat{k}}{3\sqrt{2}} = \frac{- \hat{i} + k}{\sqrt{2}}\]
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अध्याय 22: Algebra of Vectors - Exercise 23.6 [पृष्ठ ४९]

APPEARS IN

आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 22 Algebra of Vectors
Exercise 23.6 | Q 4 | पृष्ठ ४९

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