I can't seem to find this limit

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Homework Help Overview

The discussion revolves around finding a limit involving square roots and rational expressions. Participants are exploring various algebraic techniques to simplify the expression, particularly focusing on the use of conjugates and the manipulation of terms involving powers of \( n \).

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss using the conjugate method to simplify the expression but express frustration with the complexity of the resulting terms. There is also mention of dividing by \( n^2 \) to simplify the square roots, with mixed results. Questions arise about the necessity of including all terms in the denominator and whether focusing on leading terms is sufficient.

Discussion Status

The discussion is ongoing, with participants sharing their attempts and questioning the effectiveness of their approaches. Some guidance has been offered regarding the importance of focusing on the highest order terms after applying the conjugate method, but no consensus has been reached on the best way forward.

Contextual Notes

There is a note about the clarity of the original problem statement, with one participant requesting a clearer representation in LaTeX. This suggests that the presentation of the problem may be impacting the discussion.

Lavender
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Homework Statement


1.jpg

Homework Equations

The Attempt at a Solution


I tried using the rule of multiplying with the "conjugate", for example what's above multiplied by (√n^3+3n)+(√n^3+2n^2+3)/(√n^3+3n)+(√n^3+2n^2+3).
But I'm left with a huge mess :(
I also tried dividing the top and the bottom by n^2 in the square roots to get the n out, but that didn't work either :(
 
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Lavender said:

Homework Statement


View attachment 94117

Homework Equations

The Attempt at a Solution


I tried using the rule of multiplying with the "conjugate", for example what's above multiplied by (√n^3+3n)+(√n^3+2n^2+3)/(√n^3+3n)+(√n^3+2n^2+3).
But I'm left with a huge mess :(
I also tried dividing the top and the bottom by n^2 in the square roots to get the n out, but that didn't work either :(
The conjugate method looks good here. It doesn't give a mess in the numerator, right? In the denominator, do you need all the terms, or is it sufficient then only to look at the leading terms?
 
The image is so bad I can't even see the value of the exponents, try to write it out in latex next time.
Assuming what you wrote is ##\frac{\sqrt{n^3+3n}-\sqrt{n^3+2n^2+3}}{\sqrt{n+2}}##
multiplying with the conjugate works for me. After you done that note that only the "highest order" terms matter.
 
Lavender said:
I also tried dividing the top and the bottom by n^2 in the square roots to get the n out, but that didn't work either :(
After you multiply by the conjugate, you want to pull the highest power of n, not ##n^2##, out of each of the square roots.
 

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