To solve this problem you must apply the proccedure shown below:
1. When you graph the function
, you obtain the graph attached.
2. As you can see in the graph, the curve of the function tries to touch
but it never does. Therefore, the horizontal asymptote is
.
Therefore, the answer is:
![y=3](https://img.qammunity.org/2019/formulas/mathematics/college/h1ntjml4oyxqh6y1s6a81ukqjmf46v42ls.png)