WEBVTT
1
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in this problem were given a two by two matrix
2
00:00:03.049 --> 00:00:09.009 A:middle L:90%
, and our goal or task is to find the
3
00:00:09.009 --> 00:00:16.589 A:middle L:90%
determinant. So to do this we focus on the
4
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diagonals of our two by two matrix in the blue
5
00:00:19.899 --> 00:00:22.059 A:middle L:90%
direction. We would have a positive value in the
6
00:00:22.059 --> 00:00:25.239 A:middle L:90%
red direction. We have a negative as the formula
7
00:00:25.239 --> 00:00:28.429 A:middle L:90%
, remember, for a determinant is a times D
8
00:00:28.480 --> 00:00:32.500 A:middle L:90%
minus B times c. So to calculate the determinant
9
00:00:32.509 --> 00:00:35.490 A:middle L:90%
of this particular problem, we would have six times
10
00:00:35.500 --> 00:00:40.240 A:middle L:90%
three minus four times negative one and all you need
11
00:00:40.240 --> 00:00:43.119 A:middle L:90%
to do a simplify piece by piece six times three
12
00:00:43.200 --> 00:00:48.909 A:middle L:90%
is 18 minus four times negative. One is negative
13
00:00:48.909 --> 00:00:52.390 A:middle L:90%
. Four. The double negative turns into a positive
14
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18 plus four results in 22. The determinant for
15
00:00:57.200 --> 00:00:58.850 A:middle L:90%
this matrix is 22.