You are Here: Home >< Maths

Limits Question watch

1. So the question is:

Find the limit as x approaches negative infinity for: ((2-x)^2)e^x

I am not sure whether I completely understand but can you not just say as x approaches negative infinity, e^x approaches 0 and so the limit = 0

Thanks for any help.
2. (Original post by jurd1)
So the question is:

Find the limit as x approaches negative infinity for: ((2-x)^2)e^x

I am not sure whether I completely understand but can you not just say as x approaches negative infinity, e^x approaches 0 and so the limit = 0

Thanks for any help.
in a nutshell absolutely correct

exponential decay kills algebraic growth ...
3. Did you mean this function?

If that is the case, so the limit is 0, if - infinity.

Just because the graph is approaching 0 by increasing negative values of x. Plot the graph and do the math!
4. (Original post by jurd1)
So the question is:

Find the limit as x approaches negative infinity for: ((2-x)^2)e^x

I am not sure whether I completely understand but can you not just say as x approaches negative infinity, e^x approaches 0 and so the limit = 0

Thanks for any help.
The limit is 0, but in showing that you are using the fact that the exponential function dominates over polynomial growth.

What sort of techniques are you expected to use - i.e. is this a formal analysis course or just a high school or methods course?

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: January 29, 2015
Today on TSR

Struggling to get going with your revision?

Get going with the all day revision thread

Uni strikes! How do they affect you?

Discussions on TSR

• Latest
Poll
Useful resources

Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

How to use LaTex

Writing equations the easy way

Study habits of A* students

Top tips from students who have already aced their exams

Chat with other maths applicants

Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE