00:01
Hello, so we're given our matrix a that we go and we put out a matrix a and we put a vertical line and then we put the two by two identity matrix.
00:10
Now to find the inverse, what we want to do is you want to convert the left hand side to the identity.
00:16
And then what we have on the right hand side will then be our inverse matrix.
00:20
So we use elementary raw operations to do that.
00:23
So, but this matrix is going, we're going to see that it's not invertible.
00:26
So if we try to convert this and put the identity on the left hand side, well, we want to have a 1 in our leading spot and then 0 is beneath it.
00:37
So how about let's do negative 1 3rd times row 1, right, is going to put a 1 here.
00:47
So for row 1, let's do is equal to, let's say, so negative 1 3 times row 1.
00:53
So negative row 1 over 3.
00:57
And then for row 2, 1 have 0 is beneath it...