00:01
Okay, so we have this function, f of x is equal to x plus 9 divided by x squared minus 1, and we want to find the domain of this function.
00:08
So the only problem that we could run into here is dividing by 0.
00:12
We don't want to divide by 0.
00:14
So we want to avoid the case where x squared minus 1 is equal to 0.
00:18
So let's factor rate x squared minus 1.
00:21
We can write this as x plus 1, x minus 1.
00:26
So x squared minus 1 equals 0 when x equals 1 or x equals minus 1.
00:36
Okay, so these are the only two problems, the only two points which are going to cause us problems.
00:41
Every other point, this function is perfectly well defined.
00:44
The only problem is dividing by 0, and this happens when x is equal to 1 or x is equal to minus 1...