00:01
Okay, in order to find the answer for this, what i'm going to do is, since determinant of whatever it's inside, square, i can always write it as a determinant of b inverse a, b, times determinant of b inverse a, b.
00:26
Okay? so trying to make it smaller pieces.
00:32
We know the determinant of a, b, and since we know what the formula is for determinant of b inverse, i can make this only.
00:43
I'm just going to go focus on one of these because they're going to be equal.
00:47
So this is i can write to determinant of b inverse times determinant of a times determinant of b.
01:03
Okay and this whole thing has to be multiplied by the same thing i'm not going to write that so i know that determinant of b inverse since i have determined let me write the determinant of a they're giving us the determinant a what is it let me look at the problem it is three so i know this is three times the term of b is minus four okay and i know the inverse of determinant is going to be one over minus four okay...