00:01
So in this problem, we're given these three vectors, u, v, and w, where u is 1 -1 -2, v is negative 2 -3 -1, and w is 2 -9 -1.
00:12
And we're asked to determine in a set of vectors here, which ones are linear combination of u -v -w.
00:45
Let's look for a second at the z.
00:53
Look at the z component.
01:00
All right.
01:02
So if we do, then we have the z is.
01:09
So you notice that w, it's 2 negative 1 -1, right? okay.
01:29
And in u, it's 1 -1 -2.
01:40
V, it's negative 2 -3 -1.
01:42
All right.
01:43
So we can set this up.
01:45
As two times the sum of the x components which will be x plus okay so let's let's look for a second let's take that off if we look at the z component for each one of these what do we notice in u in the vector u we notice that x plus y is z one plus one equals two okay what about in v again we got x plus y because we get negative two plus three is equal to one and look at it in w it's x plus y as well two minus one is one okay so any linear combination will have z is equal to to x plus y.
03:30
No matter how we add these three together, no matter what we multiply them by and all, it's still going to have that relationship happen in it.
03:39
So let's now look at the points that are given.
03:43
So 0 -1 -1.
03:47
Well, x plus y is 0 plus 1, which is 1, which is not equal to 0.
03:57
So not that one.
04:02
Let me put it this way.
04:04
Let me say not.
04:08
Okay.
04:10
Then let's look at 1 -0 -0.
04:14
Again, x plus y...