Results 1 to 3 of 3

Math Help - quick vector problem

  1. #1
    Newbie
    Joined
    Jan 2008
    Posts
    11

    quick vector problem

    Determine ||v+w|| if v and w are unit vectors separated by 0.3 radians
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Member
    Joined
    Aug 2008
    Posts
    120
    First thing to do is draw a diagram of the triangle. Two sides are 1 and the angle between them is \pi-0.7. Use cosine rule to find the distance required.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Super Member
    earboth's Avatar
    Joined
    Jan 2006
    From
    Germany
    Posts
    5,830
    Thanks
    123
    Quote Originally Posted by casesam View Post
    Determine ||v+w|| if v and w are unit vectors separated by 0.3 radians
    Let \vec w = (1, 0)

    Since |\vec w| = |\vec v| you can express \vec v as:

    \vec v = |\vec w|(\cos(0.3), \sin(0.3))

    Therefore

    \vec v + \vec w = |\vec w|(1+\cos(0.3), \sin(0.3))

    Now calculate

    |\vec v + \vec w| = |\vec w|\sqrt{(1+\cos(0.3))^2+(\sin(0.3))^2}\approx 1.9778 because |\vec w| = 1.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. quick vector question
    Posted in the Algebra Forum
    Replies: 4
    Last Post: April 14th 2010, 07:40 AM
  2. Quick vector question
    Posted in the Algebra Forum
    Replies: 5
    Last Post: April 12th 2010, 03:45 AM
  3. Quick vector question
    Posted in the Geometry Forum
    Replies: 1
    Last Post: October 7th 2009, 12:02 PM
  4. quick vector field question
    Posted in the Calculus Forum
    Replies: 4
    Last Post: September 23rd 2009, 01:42 PM
  5. quick vector calc question
    Posted in the Calculus Forum
    Replies: 5
    Last Post: September 21st 2009, 01:34 PM

Search Tags


/mathhelpforum @mathhelpforum