00:01
To evaluate the determinant of a 3x3 matrix, we have a little trick.
00:05
We know that there should be of a 3 by 3 matrix, there should be 3 factorial terms.
00:11
So that would be 3 times 2 times 1.
00:14
So there's 6 terms total.
00:15
So one trick to do use when looking at a 3x3 matrix is to just rewrite the first two columns over here.
00:24
Again, so we have 0 ,0, 0, and negative 2, 1.
00:29
And now we'll find our six terms by looking diagonally down these columns.
00:40
So you'll multiply all the values in these columns.
00:44
So the three edges circled, multiply those terms together and add them.
00:50
And then you subtract these terms.
00:58
It's going to be three positive terms and three negative terms.
01:01
So it's going to be subtracting...