Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Direction vector of a line

  1. Jun 8, 2006 #1
    How would I find the direction vector of a line given in the form ax + by + cz +d =0?

    Thankyou.
     
  2. jcsd
  3. Jun 8, 2006 #2

    TD

    User Avatar
    Homework Helper

    I see an equation of a plane, not a line.
     
  4. Jun 8, 2006 #3
    Damn, sorry, got carried away with my letters. I meant ax + by +c = 0. Sorry about that...
     
  5. Jun 8, 2006 #4

    TD

    User Avatar
    Homework Helper

    For a line, (1,m) is always a directional vector where m is the slope. Can you find the slope?
     
  6. Jun 8, 2006 #5
    Yeah - I thought it would be something simple like that. Thanks for your help.
     
  7. Jun 8, 2006 #6

    TD

    User Avatar
    Homework Helper

    You're welcome :smile:
     
  8. Jul 20, 2008 #7
    Thanks for asking that Q, it helped me too
     
  9. Jul 21, 2008 #8

    Defennder

    User Avatar
    Homework Helper

    I don't think there's a need to thank someone who started a thread two years ago and have not posted since.
     
  10. Jul 23, 2008 #9
    LORL.... Thanks for pointing that out. ( At least you still logon)
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook