Find all the minors of the elements in the matrix.

Question

Find all the minors of the elements in the matrix.

[2 4 -1

0 9 2

-3 5 0]

M11=

M12=

M13=

M21=

M22=

M23=

M31=

M32=

M33=

Answer 1

To find a minor of a matrix first eliminate all values in both the row and column from where you start the minor.

For M₁₁ start at the value 2 and remove all numbers above below and to the sides.

All that will remain is

[9 2

5 0]

Then find the determinant.

9 * 0 - 5 * 2 = -10

Again for M₁₂ Start at the 1st row 2nd column. (Number 4)

Remove all vertical and horizontal numbers until you are left with.

[0 2

-3 0]

The determinant of this is 6

So M12 = 6