00:01
So in this problem, the first thing we're asked to do is find the inverse for the given function.
00:04
So remember, to find the inverse of a function, we have to switch our x and y values.
00:09
Keep in mind that f of x is the same as y.
00:12
So we'll start by replacing y with x, and we replace our x's with y's, so a y squared minus 6y.
00:19
So now to find the inverse, we just have to solve this equation for y.
00:23
To do this, we're going to use the completing the square method to have a perfect square trinomial on the right -hand side.
00:29
So to find this constant, we have to do the formula b over 2 square, where b is the coefficient of our middle term.
00:36
So we have negative 6 divided by 2, which is negative 3, and negative 3 when we square it is positive 9.
00:43
So not only do we add 9 to the right, but we also have to add 9 to the left to keep this balanced.
00:49
So we're going to have x plus 9 equals.
00:51
Well, now on the right hand side, we can factor this trinomial.
00:55
Remember, it's a perfect square trinomial.
00:57
So it will factor to one binomial that's being squared...