1. Not finding help here? Sign up for a free 30min 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!

Coordinates and change of base

  1. May 12, 2012 #1
    1. The problem statement, all variables and given/known data
    Screenshot2012-05-12at100357PM.png



    3. The attempt at a solution

    I don't understand where 2v1 + 3v2
    and
    4v1 - 3v2

    came from.
     
  2. jcsd
  3. May 12, 2012 #2
    I see that the vectors are raised to T which I'm pretty sure means they're transposed but that still doesn't get me anywhere.
     
  4. May 13, 2012 #3

    sharks

    User Avatar
    Gold Member

    Where's Figure 3.29a? You should post the whole example to help us get a clearer picture of the problem.
     
  5. May 13, 2012 #4

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    You are solving the equations
    [tex]x= \begin{bmatrix}11 \\ 7\end{bmatrix}= a\begin{bmatrix}1 \\ 2\end{bmatrix}+ b\begin{bmatrix}3 \\ 1\end{bmatrix}[/tex]
    which is the same as the two equations a+ 3b= 11 and 2a+ b= 7. Can you solve for a and b?
    And
    [tex]y= \begin{bmatrix}-5 \\ 5\end{bmatrix}= c\begin{bmatrix}1 \\ 2\end{bmatrix}+ d\begin{bmatrix}3 \\ 1\end{bmatrix}[/tex]
    which is the same as the two equations c+ 3d= -5 and 2c+ d= 5. Can you solve for a and b?
     
    Last edited by a moderator: May 13, 2012
  6. May 13, 2012 #5
    ok, thanks, I got it now.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Coordinates and change of base
Loading...