00:01
We're doing a curve -fitting question again, so let's create our four equations.
00:05
So, negative 112 is equal 2, negative 3k, negative 207a, plus 3 squared, it is 9b, minus 3, 2 plus b.
00:19
There's our first one.
00:21
Our typing 1 is that negative 2 is equal 2, negative 1 key, negative a.
00:30
B, 2.
00:32
1 plus b.
00:35
And then for our third one, we've got 4 is equal to 1 squared with a, t, b, and d.
00:44
So for our last one, 13, is equal to 2 of 2 which is 8, 2 squared which is 4, 2, and b.
00:55
Now we can create our matrix.
01:00
8 .279.
01:10
1 ,1, 2, 1, 2, 1, 1, 1, 4.
01:18
And last 3, 8, 4, 2, 1, 2, 1.
01:23
So, there's our matrix.
01:28
So let's get out.
01:30
So why don't we use row 3 as our main row? so we're going to go 1 plus 1, 2 ,7, 0433.
01:38
Row 2 plus row 1, and row 4 minus 8 row 1.
01:47
Cut all those numbers out above and below.
01:51
0, 9 plus 27 is 36, negative 3 plus 27 is 24, and 1 plus 27 is 28.
02:06
1 for our answer.
02:09
Negative 112 plus 4 times 0 .7 is negative 4.
02:17
For our next row, even 1 plus 1 is 0.
02:21
1 plus 1 is 2, negative 1 plus 1 is 0, 1 plus 1 is 2.
02:26
Negative 2 plus 4 is 2.
02:30
For our third row, we haven't changed anything.
02:34
4th row, 8 minus 8 is 0, 4 minus 8 is negative 4, 2 minus 8 is negative 4, 2 minus 8 is negative 6, 1 minus 8, 0 .8, 97.
02:44
13 minus 8 times 4, and negative 19.
02:53
All right, we are going to first row all divides by 4, or the second row all divides by 2.
03:01
I'm going to take a quarter on my first row.
03:09
0, 9, 6, 7, 9, 0, 0, 0, 0 ,0, 1, 0, 0, 0, 0, 0, 0, 0, 9, 6, 7, 7, 7, 7, 7, 7, 0, 7, 0, 7, 0, 7, 7, 0, 7, 0, 7, 0, 7, 0, 7, 7, 0, 7.
03:26
All right, so why don't we do a two -secker again? we're going to take our second row and use it to get rid of the numbers above and below it.
03:38
First row minus our second row, third row minus the second row, and the fourth row plus four of our five.
03:51
So you can do them all in one set, or you can do them all those three separate vacations...