Finding Limit: Hi, I've Got 2 Questions

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SUMMARY

The discussion focuses on two limit problems involving calculus. The first problem requires finding the limit as x approaches 0 of the expression [(e^4x)-1-4x]/x^2, which is initially an indeterminate form 0/0. The correct application of L'Hôpital's Rule leads to the conclusion that the limit is 8. The second problem involves finding the limit as x approaches 2 of (x+2)/[(x-2)^4], which results in a vertical asymptote since it evaluates to 4/0. L'Hôpital's Rule is not applicable here due to the absence of a 0/0 indeterminate form.

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Hi, I've got two questions here that I'm stuck on.
The first:

Homework Equations


Find the Limit as x->0 of [(e^4x)-1-4x]/x^2


The Attempt at a Solution


So far:
I got that the Limit as x->0 is indeterminate form 0/0 so I tried L'Hopital's:

to find the Limit as x->0 of [(e^4x)-4]/2x

but that gave me a Limit of -3/0 . So I think that means that there's no limit. But the book insists that the Limit is 8. and I have no idea how it got there.


the second question I'm confused about is

Homework Equations


Find the Limit as x->2 of (x+2)/[(x-2)^4] , and explain why L'Hopital's Rule does not apply.


The Attempt at a Solution


so
The Lim x->2 = 4/0 so it's not 0/0 indeterminate so L'Hopital's isn't applicable.

But after that I'm a bit stuck on how to get the Limit. I know that because x can't equal 0 in the denominator that x cannot equal 2. So there's a vertical asymptote there.
So...I know I can look at it from each side
The Limit as x->0- and as x->0+ .
So-
The Limit as x->0+=infinity
The Limit as x->0-=infinity.
is that right? and is their an easier way to find that then just plugging in numbers near x=2?

-Thanks, any help would be much appreciated!
 
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The derivative of e^(4x) is 4e^(4x)... correct this and it should work out.
 

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