How to find horizontal asymptotes?

[hahaha158]

Homework Statement

f(x)=(8-4x)e^x

Homework Equations

The Attempt at a Solution

I know you can usually compare the top and bottom and determine that way but how can you do it when it's like this? I know the answer is 0 already i don't know how to get it though

 

[Robert1986]

Do you see how you might be able to re-write this and then use L'Hospital's Rule?

Edit:
Just as a side note, I hope you realize that there is no horizontal asymptote as x goes to positive infinity.

 

[hahaha158]

Do you see how you might be able to re-write this and then use L'Hospital's Rule?

Edit:
Just as a side note, I hope you realize that there is no horizontal asymptote as x goes to positive infinity.

ah i think i got it.

do you end up with -4/(-1/e^(-x)) which basically is equal to -4/-infinity = 4/infinity = 0?

 

[Robert1986]

Yes, but just to say it again, it is not as x goes to positive infinity.