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#1 2011-02-27 19:34:03
- sami4
- Member
- Registered: 2010-11-30
- Posts: 7
Limits
Hi,
I am having trouble with this limit, and I would appreciate anyone's imput.
limit (1+(1/3X))^(7+2X)
as x->0
I have tried to manipulate this into the 2 indeterminate forms that work with L'hopitals rule to no avail.
I am leaning toward the limit approaching 0 , since the limit is undefined at x=0, if we approach x from 0+, the limit goes to infinity^7 , which means 1/[(inifinity)^-7)] = 0
Thank you for your help
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#2 2011-02-27 19:43:56
- gAr
- Member
- Registered: 2011-01-09
- Posts: 3,482
Re: Limits
Hi sami4,
If you meant 1/3x to be 1/(3x), answer is infinity. If it is (1/3)x, answer is 1.
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?
"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
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#3 2011-02-27 19:49:16
- sami4
- Member
- Registered: 2010-11-30
- Posts: 7
Re: Limits
I meant 1/3x,
however ,I think the answer is not infinity. Infinity is not one of the options in the possible multiple choices. I think l'hopital might have to be used. However, as I said, I am having trouble getting it into the indeterminate form
The possible answers are :
a)0
b)1
c)e^7
d)e^(2/3)
e)7
Last edited by sami4 (2011-02-27 20:22:55)
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#4 2011-02-27 19:55:47
- sami4
- Member
- Registered: 2010-11-30
- Posts: 7
Re: Limits
here is a clear image of the limit
http://img35.imageshack.us/i/60400746.png/
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#5 2011-02-27 21:20:54
- gAr
- Member
- Registered: 2011-01-09
- Posts: 3,482
Re: Limits
Hi sami4,
The brackets in your image and text do not match.
I'll asssume:
If the limit is approached from negative direction, you'll get a complex number(both real and imaginary parts approach -∞).
From positive direction, it's +∞
Are you sure about the question?
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense" - Buddha?
"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."
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