How to Find the Unit Vector of a Given Vector?

AI Thread Summary
To find the unit vector u in the direction of vector v = <3, -4>, first calculate the magnitude of v, which is 5. The unit vector is obtained by dividing each component of v by its magnitude. Thus, the unit vector u is expressed as u = <3/5, -4/5> and u = (3/5)i - (4/5)j. This confirms that the unit vector has a length of 1, aligning with the definition of a unit vector. The solution effectively demonstrates the process of finding a unit vector from a given vector.
huntingrdr
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Homework Statement


Given vector v = <3, -4>, find a unit vector u in the direction of vector v. Give your answer for u as
u = <a, b>
and
u = ai + bj



Homework Equations



none

The Attempt at a Solution



Would I use y2-y1 and x2-x1?
 
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Do you know how to find the length of a vector? If so, use the fact that any vector divided by its length will have a length of 1 (i.e., it will be a unit vector).
 
A unit vector is given by a vector divided by its magnitude. To find a vector's magnitude, or length, use v=sqrt[x^2+y+2].
 
OK, so I got the magnitude of the vector to be 5. So does that mean the answer would be 3/5 i - 4/5 j and <3/5 , -4/5>
 
That's it!
 
Thanks!
 
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