00:01
All right, we have a rational function here.
00:02
We've got f of x is equal to x plus 1 divided by x squared plus x minus 2.
00:17
First, we need to determine the symmetry of the function.
00:21
So we need to check for three symmetries, as you know, you have your options there.
00:26
You can see.
00:27
So we want to check for symmetry.
00:30
I notice your first option is with respect to the origin.
00:38
Okay, so to check for symmetry with respect to the origin, you replace each y with negative y and each x with negative x and see if you get an equivalent function.
00:55
So we're going to use y instead of f of x.
00:58
So we have negative y is equal.
01:01
Equal to negative x plus 1 divided by negative x squared plus negative x minus 2.
01:13
So let's simplify this and see what we have.
01:17
If i multiply both sides by a negative 1, i would get y is 1 minus x squared minus x minus 2.
01:31
So that's not the same because i have have a plus right here and a negative right here and plus, you know, x plus one is not the same as 1 minus x.
01:44
So we do not have symmetry with respect to the origin.
01:50
Now we want to find out if it's, do we have symmetry with respect to the y -axis? so now if we want to check for the y -axis, we're going to replace x with negative x.
02:06
Whoops.
02:07
And see if we get an equivalent function.
02:10
So, y is equal to negative x plus 1 divided by negative x squared plus a negative x minus 2.
02:25
And so we get negative x, well, let's write it as 1 minus x over x squared, minus x minus 2.
02:38
So same problem, right? this is not equivalent.
02:42
X plus 1 is certainly not the same as 1 minus x, and we have a negative sign right there.
02:49
So here you have a c.
02:58
The graph of f has neither y axis symmetry nor symmetry about the origin.
03:07
Okay, then we're asked to find the y.
03:09
Intercept.
03:11
Well, remember, the y intercept is going to be when x is equal to zero.
03:16
So we just need to take our function and set x equal to zero.
03:21
So we get zero plus one over zero squared plus zero minus two, which is equal to negative one half.
03:30
So our y intercept is going to be zero negative one half.
03:37
And then find the x intercept.
03:42
So the x intercept is going to be when y is equal to 0.
03:46
So we set the whole function equal to 0...