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: Matrices homework problem help

  1. Nov 19, 2008 #1
    If the determinant of a 3x3 matrix A is det(A)=5, and the matrix B is obtained from A by multiplying the first column by 8, then det(B)=?

    I really haven't tried anything for this question; I'm not even sure where to start.
  2. jcsd
  3. Nov 19, 2008 #2
    Re: Matrices

    Hi Reeses,

    Start by reviewing your class notes or text: what effect does multiplying a column of a matrix by a scalar have on its determinant?
  4. Nov 19, 2008 #3
    Re: Matrices

    You might even want to try to figure it out before consulting your notes. Take a 3x3 identity matrix and see what effect multiplying a single column (or more than a single) by a scalar has on the determinant.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook