Hello, Mr_Green!

Another approach . . .

Find the range of the following function: .

We see that the graph is symmetric to the y-axis.

So we need consider only and "reflect" the graph.

There is a vertical asymptote at .

We see that: .

. . .and that: .

There is a y-intercept and no x-intercepts.

Since

. . there is a horizontal asymptote: .

The graph looks something like this: Code:

: | :
:* | *:
: | :
: * | * :
: * | * :
: * | * :
: * :
: |16/9 :
: | :
------------------:-------+-------:--------------------
-3: | :3
: | :
- - - - - - - - - : - - - + - - - : - - - - - - - - -
* : -4| : *
* : | : *
* : | : *
* : | : *
* : | : *
: | :
*: | :*

The range appears to be below and above .

As ThePerfectHacker said: .