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Question
If \[\vec{a} = 3 \hat{ i } - \hat{ j } + 2 \hat{ k } \] and \[\vec{b} = 2 \hat { i } + \hat{ j } - \hat{ k} ,\] then find \[\left( \vec{a} \times \vec{b} \right) \vec{a} .\]
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Solution
\[\text{ Since } \vec{a} \times \vec{b} \text{ is a vector, } \left( \vec{a} \times \vec{b} \right) \vec{a} \text{ without any dot or cross product in between is meaningless } .\]
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