Results 1 to 3 of 3

Math Help - Vectors

  1. #1
    Member
    Joined
    Nov 2005
    Posts
    172

    Vectors

    Consider two vectors by A = 2 i - 2 j and B = - i - 6 j.
    1) What is the direction of A + B? (from the +x axis)
    I have A + B = 1 i - 8 j, and |A + B| = 8.06,
    what i need to do to get the direction?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Rhymes with Orange Chris L T521's Avatar
    Joined
    May 2008
    From
    Santa Cruz, CA
    Posts
    2,844
    Thanks
    3
    Quote Originally Posted by viet View Post
    I have A + B = 1 i - 8 j, and |A + B| = 8.06,
    what i need to do to get the direction?
    The angle is determined by \vartheta=\tan^{-1}\left(\frac{v_y}{v_x}\right), where v_x~and~v_y are the components of a vector \vec{v}

    So, in our case, \vec{A}+\vec{B} (which I will denote as \vec{V}) is \vec{i}-8\vec{j}

    Thus, \vartheta=\tan^{-1}\left(\frac{-8}{1}\right)\approx\dots

    I hope this helps!

    --Chris
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Member
    Joined
    Nov 2005
    Posts
    172
    easier than what i expected. tyvm Chris.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 3
    Last Post: November 15th 2011, 05:10 PM
  2. Replies: 3
    Last Post: June 30th 2011, 08:05 PM
  3. Replies: 2
    Last Post: June 18th 2011, 10:31 AM
  4. [SOLVED] Vectors: Finding coefficients to scalars with given vectors.
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: January 23rd 2011, 12:47 AM
  5. Replies: 4
    Last Post: May 10th 2009, 06:03 PM

Search Tags


/mathhelpforum @mathhelpforum