1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
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: Linear Algebra, spanned by vectors

  1. Jun 23, 2008 #1
    How is this "All of R^3"

    Describe the subspace of R^3 spanned by: all vectors with positive components.

    Answer is, All of R^3. I don't get how it's all of R^3 though because if the components are all positive, it's only spanning in the positive direction? What about the negative portion? That is excluded, so it's not all of R^3.
  2. jcsd
  3. Jun 23, 2008 #2


    User Avatar
    Homework Helper

    That may be so, but the linear coefficients of the positive vectors may be negative.
  4. Jun 23, 2008 #3
    Ah, I c! Thanks.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook