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Question
Find a vector of magnitude 4 units which is parallel to the vector \[\sqrt{3} \hat{i} + \hat{j}\]
Solution
Let \[\vec{a} = \sqrt{3}\hat{i} + \hat{j}\]
Then,
\[\left| \vec{a} \right| = \sqrt{\left( \sqrt{3} \right)^2 + 1} = \sqrt{3 + 1} = \sqrt{4} = 2\]
A unit vector parallel to \[\vec{a}\] = \[\hat{a} = \frac{\vec{a}}{\left| \vec{a} \right|} = \frac{1}{2}\left( \sqrt{3}\hat{i} +\hat{j} \right)\]
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