00:01
Okay, so we have this subspace s of r4 consisting of all vectors of this form.
00:07
So a, b and c are real numbers.
00:09
We have a plus b, a minus b plus 2c, b, c, b, c.
00:14
And we want to find a basis for this and then the dimension.
00:18
So if we take an arbitrary vector in this space, it's of the form a plus b, a minus b plus 2c, b, c, and then what we're going to do is split this vector up, so each vector only contains a, b, or c.
00:34
So the first vector is going to be a, a, 0, a, 0.
00:39
The next vector is b minus b, b, b, 0, and the final vector is 02c, 0 .c, so all i've done is split this vector up into three vectors, each containing only a, b, or c.
00:59
And now this first vector, if we put out the factor of a, we get a -1 -1 -0.
01:05
The second vector, if we put out the factor of b, we get b -1 -1 -1 -0...