Determinants.

So I’m blogging today because I have a volleyball tournament in Golf Shores this weekend and I don’t know when I will be back on Sunday. And for lack of anything to blog about I will blog about Determinants. Missed you Brob, Hope you had a good trip, I heard Jacob did great!

-Notation- similar to absolute value

-If the determinant =0 then it is called a singular matrix because it doesn't have an inverse.

-For a 2X2 matrix you use ad-bc

-For a 3X3 matrix - recopy the first 2 columns, then multiply the diagonals add the right, subtract the left

-For a 4X4 matrix it may be easier to just use your calculator.

Ex.1:

find the determinant of:

2 6

1 9

2(9)-6(1)=12

Ex.2:

find the determinant of:

1 9 6 4

2 5 4 3=-123

7 0 8 6

5 2 9 8

Ex.4:

find the determinant of:

12 3=174

2 15

Ex.5:

find the determinant of:

0 1 2 3

2 0 1 4=25

6 2 3 1

1 0 0 3

--Danielle