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Question
If \[\left| \vec{a} \right| = 2, \left| \vec{b} \right| = 3 \text{ and } \vec{a} \cdot \vec{b} = 3,\] find the projection of \[\vec{b} \text{ on } \vec{a}\]
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Solution
\[\text{ We have }\]
\[\left| \vec{a} \right| = 2 \text{ and } \vec{a} . \vec{b} = 3\]
\[\text{ So,the projection of } \vec{b} \text{ on } \vec{a} \text{ is }\]
\[\left( \frac{\vec{a} . \vec{b}}{\left| \vec{a} \right|} \right)\]
\[ = \frac{3}{2}\]
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