00:01
The triple scalar product of three vectors is shown as parentheses with the three vectors in there.
00:09
And what this is defined to be is it is defined to be a dotted into the cross product between the last two vectors.
00:22
However, it is also defined to be several other things.
00:26
So you may exchange the dot and the crossed.
00:33
So it is also a cross b dotted into d.
00:38
And it is also equal to the determinant with each row in that matrix for which you're finding the determinant occupied by one of the vectors.
00:54
So the first vector occupies the first row.
01:00
Second vector, the second row, et cetera.
01:04
And you know that the determinant just changes sign depending on how many rows or columns you've exchanged or swapped.
01:15
But we'll go ahead and use the determinant definition.
01:21
Can be a little bit quicker than the dot product could be, but it's a nicely organized matrix.
01:31
So we put our components of a, a, b, and d are shown as off to the left.
01:39
B is 3 minus 4 and 0, and d is 6 2 minus 3.
01:47
And those zeros are going to make things a little bit easier to deal with.
01:52
So there are really only two sub -determinants that we have to deal with.
01:56
The first comes from blocking out the first row...