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Homework Help: The angle that A makes with the positive x axis

  1. Sep 6, 2011 #1
    A=2i-10k

    give the angle that A makes with the positive x axis ?


    do i need to make x axis=i and i go A.B/AxB ?
     
  2. jcsd
  3. Sep 6, 2011 #2
    You have short sides of a triangle, you want the inverse tangent, see:

    http://math12.vln.dreamhosters.com/wiki/Modeling_Real_World_Situations_Using_Trigonometric_Functions#Tangent_of_Theta [Broken]
     
    Last edited by a moderator: May 5, 2017
  4. Oct 6, 2011 #3
    Is this 3-dimesional question?
     
  5. Oct 6, 2011 #4

    NascentOxygen

    User Avatar

    Staff: Mentor

    It is. But don't be put off, because it's actually an easy 3D question. :smile:
     
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