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Question
If \[\vec{a,} \vec{b}\] represent the diagonals of a rhombus, then
Options
\[\vec{a} \times \vec{b} = \vec{0}\]
\[\vec{a} \cdot \vec{b} = 0\]
\[\vec{a} \cdot \vec{b} = 1\]
\[\vec{a} \times \vec{b} = \vec{a}\]
Solution
\[\text{ We know that the diagonals in a rhombus } ( \vec{a} \text{ and } \vec{b} ) \text{ are perpendicular } .\]
\[\text{ Therefore, their dot product is zero} .\]
\[ \Rightarrow \vec{a} . \vec{b} = 0\]
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