How do you find the unit vector having the same direction as vector $u=3i-4j$ ?

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Answer 1 · 2016-07-28T15:33:14

Unit vector $-> 3/5i-4/5j$

Tony B

This question type is asking: What would the value of i and j be if the vector length was 1.

Current vector length is $" "sqrt(3^3+(-4)^2) =sqrt(25)=5$

The | | notation means 'Cardinality' which is another name for magnitude. So

$|3i-4j|=5$ but we need a length of 1 so

unit vector $= |(3i)/5-(4j)/5|=5/5 = 1$

How do you find the unit vector having the same direction as vector u=3i-4ju=3i-4j?