00:01
So in order for us to determine what this smallest possible dimension of null a could be, we can use the following.
00:11
So we can use the fact that we know the rank, rank of a plus the dimension of the null of a should be equal to, so over here if this is m by n, it should be equal to n.
00:29
So if we can figure out, well, what should our maximum rank of this be, then we can use that to find our minimum dimension.
00:39
Because max rank is saying the same thing as minimizing our null a dimension.
00:47
So let's go in and just draw six by four matrix.
00:50
So one, two, three, four, five, six.
00:54
So six rows and then four columns everywhere where the red and green light intersect each other...