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Homework Help: Vector problem

  1. Jun 28, 2016 #1
    1. The problem statement, all variables and given/known data
    the angles which
    î + ĵ + √2k̂ makes with x axis, y axis and z axis are?

    3. The attempt at a solution
    the question is basically asking us what angle î + ĵ + √2k̂ makes with î + ĵ + k̂ right?
    So since √2 is just the magnitude i thought the answer would be 90, 90, 90
    the answer given is 60, 60 and 45

    PS: i just started learning vectors
    Last edited: Jun 28, 2016
  2. jcsd
  3. Jun 28, 2016 #2
    î + ĵ + √2k̂ is a vector made up of three components, but it corresponds to a single vector. From my interpretation of the question, I would assume the question expects three answers (which is seems like it does). Rather than finding the angle î + ĵ + √2k̂ makes with î + ĵ + k̂ you are finding:
    a). The angle î + ĵ + √2k̂ makes with î
    b). The angle î + ĵ + √2k̂ makes with ĵ
    c). The angle î + ĵ + √2k̂ makes with
  4. Jun 28, 2016 #3


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    Homework Helper

    ##\sqrt{2}## is the coefficient of the unit vector k.

    To calculate the magnitude of the vector ##i + j + \sqrt{2} k##, you still have to do some further calculations.

    What you are looking for are the direction cosines of this vector:

  5. Jun 28, 2016 #4
    oh i had completely misinterpreted the question! Thanks for the help @Yosty22
  6. Jun 28, 2016 #5
    I got the answer after reading up about direction cosines! Thanks for the help @SteamKing
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