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Homework Help: Please Help: Finding Scalars from Vectors

  1. Sep 14, 2004 #1
    A=6i-8j m, B= -8i=3j m

    I know how to add and multiply vectors, but how do I find the two scalars of a and b?
    Also, I can’t figure out how to find the unit vector and direction of Resultant Vectors.

    Please Help!


  2. jcsd
  3. Sep 14, 2004 #2


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    Science Advisor

    What two scalars of a and b?

    I will assume that you really meant A and B, rather than a and b, but still there are many ways to get scalars from vectors. I am less sure about assuming that you meant the length of the vectors. That is defined as the square root of the sum of the squares of the components.

    In particular, if A=6i-8j m(eters?) then the length of A is |A|= [itex]\sqrt{6^2+ (-8)^2}= \sqrt{36+64}= \sqrt{100}[/itex]= 10 meters.

    If B= -8i=3j m (this was supposed to be -8i+ 3j, right?), then the length of B is
    |B|= [itex]\sqrt{(-8)^2+ 3^2}= \sqrt{64+9}= \sqrt{73}[/itex] meters.
  4. Sep 14, 2004 #3
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