calc problem that really has nothing to do with calc :)

[BigToque]

I'm trying to find a limit:

This is the question (I saved it as am image because it's easier to see the question that way).

I understand I'm supposed to divide both the numerator and the denominator by the largest power of x in the denominator, but I'm not sure what that is (the square root is throwing me off).

Would it be just X? (like X^1)

 

[Pokey007]

The answer is 403

 

[BigToque]

i fixed the link

 

[MaxFusion16]

l'hopital

 

[GoodToGo]

Answer is infinity.

 

[ClueLis]

The largest power is indeed 1. The answer is infinity.

 

[GoodToGo]

Originally posted by: Pokey007
The answer is 403

LMAO

 

[Pokey007]

-1/2

 

[ClueLis]

Originally posted by: MaxFusion16
l'hopital

It doesn't qualify for using L'Hopital's rule, as you have infinity-infinity on the bottom, which wouldn't work.

 

[jessicak]

Originally posted by: Pokey007
-1/2

yeah -1/2 is the answer

 

[DrPizza]

Originally posted by: Pokey007
-1/2

Pokey is correct.

 

[BullsOnParade]

nm : left out the -1 in the numerator !

 

[DrPizza]

BTW, what an interesting function for a limit! As x -> +infinity, the limit approaches infinity.

 

[DrPizza]

quick explanation for you though:

numerator can be approximated by x for really large (albeit negative) values of x.
(when you're talking about -100000000000 and -100000000001, the 1 doesn't make much of a difference.)

the square root part of the denominator will approach |x| (it'll be positive since you're squaring x and then taking the square root) And, -x is of course |x| since x is negative. Thus the denominator will be approximately twice the size of the numerator (and positive) while the numerator will be negative.
So, -1/2

 

[Pokey007]

Originally posted by: DrPizza
quick explanation for you though:

numerator can be approximated by x for really large (albeit negative) values of x.
(when you're talking about -100000000000 and -100000000001, the 1 doesn't make much of a difference.)

the square root part of the denominator will approach |x| (it'll be positive since you're squaring x and then taking the square root) And, -x is of course |x| since x is negative. Thus the denominator will be approximately twice the size of the numerator (and positive) while the numerator will be negative.
So, -1/2

yup

 

[BigToque]

I still don't understand the steps that I am supposed to follow.

I know that I need to divide the numerator and denominator by the largest power of x in the denominator, I just dont know how to get (or find out) what the largest power of x is.

My problem isnt the "calculus" part, it's the algebra that's my problem. I never took pre-calc.