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: Matrix calculation help

  1. Aug 5, 2010 #1
    The question just says "Calculate" followed by these:

    a)
    |a+b -b|
    | b a-b|

    b)
    | 2 4-n|
    | 1 2 |

    c)
    |0 a 0|
    |0 0 b|
    |c 0 0|

    In the question the lines at the edges are joined up, but not brackets. I don't know what to calculate or how to do it. A worked example would be helpful!
     
  2. jcsd
  3. Aug 5, 2010 #2

    ehild

    User Avatar
    Homework Helper

    Re: Matrix

    These things between two vertical lines can be determinants. Look after, how to calculate the value of a determinant.

    ehild
     
  4. Aug 5, 2010 #3
    Re: Matrix

    So for part a) would the answer be: a^2 - 2b^2 ?
     
  5. Aug 5, 2010 #4

    ehild

    User Avatar
    Homework Helper

    Re: Matrix

    Not quite... You have to subtract (-b^2).

    ehild
     
  6. Aug 5, 2010 #5
    Re: Matrix

    oh yeah, woops, so it's actually just a^2?
     
  7. Aug 5, 2010 #6

    Mark44

    Staff: Mentor

    Re: Matrix

    Yes.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook