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Homework Help: Vector Sum x,y and angle

  1. Feb 3, 2012 #1
    1. The problem statement, all variables and given/known data
    The two vectors a and b in the figure have equal magnitude of 29 m and the angles are θ1 = 31° and θ2 = 105°. Find the x-component of their vector sum r. Find y-component sum. Magnitude of the vector sum? Find the angle that their vector sum r makes with the positive direction of the x-axis.

    2. Relevant equations

    3. The attempt at a solution

    Ok i am confused as to why this won't work.
    x = 29cos31 + 29cos105
    y = 29sin31 + 29sin105

    The second vector/magnitude points towards the y axis and the first one points away. i can not seem to insert a picture.
  2. jcsd
  3. Feb 3, 2012 #2
    Looks good to me. Why do you think that's wrong? I'm assuming you're not making a simple mistake like confusing degrees and radians.
  4. Feb 3, 2012 #3
    i mean i think it is right. i put that answer into lon capa and it said it was wrong, so i figured i was doing something wrong.
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