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Homework Help: Vector 3ax+5ay-8az

  1. Jan 12, 2006 #1
    i have a vector h whose value is 3ax+5ay-8az where a is the unit vector in the direction beside it, how would i find the angle between this vector and the x,y,and z axes
  2. jcsd
  3. Jan 12, 2006 #2
    Do you mean h = 3x + 5y - 8z ?

    In any case, in order to find the angle between vectors, take the dot product.

    Eg. Angle between h and x- axis would be given by:

    h . (unit vector x) = (magnitued of h) * cos (theta)
  4. Jan 12, 2006 #3
    Or, you can find the sq. root of the sum of the squares (3^2+5^2+(-8)^2)^0.5

    and then for each direction divide the magnitude by this value and it will give you the cos for each angle
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