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Question
\[\vec{a} \text{ and } \vec{b}\] are two vectors such that \[\vec{a} . \vec{b} = 6, \left| \vec{a} \right| = 3 \text{ and } \left| \vec{b} \right| = 4 .\] Write the projection of \[\vec{a} \text{ on } \vec{b}\]
Solution
We have
\[ \vec{a} . \vec{b} = 6 \text{ and } \left| \vec{b} \right| = 4\]
\[\text{ The projection of } \vec{a} \text{ on } \vec{b} \text{ is }\]
\[\frac{\vec{a} . \vec{b}}{\left| \vec{b} \right|}\]
\[ = \frac{6}{4}\]
\[ = \frac{3}{2}\]
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