Results 1 to 2 of 2

Math Help - division explanation

  1. #1
    Member
    Joined
    Sep 2009
    Posts
    181

    division explanation

    Hello,

    I was wondering... Why is it divided by n^2? This is actually a calculus problem, trying to determine if the series is convergent or divergent.

    But, I just needed some clarification on the algebra.

    Thanks,division explanation-algebra.jpg
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member

    Joined
    May 2006
    From
    Lexington, MA (USA)
    Posts
    11,865
    Thanks
    744

    Re: division explanation

    Hello, l flipboi l!

    Why is it divided by n^2?

    \lim_{n\to\infty}\frac{n}{\sqrt{10+n}} \;=\;\lim_{n\to\infty}\dfrac{1}{\sqrt{\dfrac{10}{n  ^2}+\dfrac{1}{n}}} \;=\;\infty

    We have the fraction: . \frac{n}{\sqrt{10+n}}

    \text{Divide top and bottom by }n\!:

    . . \dfrac{\dfrac{n}{n}}{\dfrac{\sqrt{10+n}}{n}} \;=\;\dfrac{1}{\dfrac{\sqrt{10+n}}{\sqrt{n^2}}} \;=\;\frac{1}{\sqrt{\dfrac{10+n}{n^2}}} \;=\;\frac{1}{\sqrt{\dfrac{10}{n^2} + \dfrac{n}{n^2}}} \;=\;\frac{1}{\sqrt{\dfrac{10}{n^2} + \dfrac{1}{n}}}

    Got it?

    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. I need an explanation
    Posted in the Pre-Calculus Forum
    Replies: 2
    Last Post: February 1st 2010, 09:09 PM
  2. Need some help and explanation...
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: July 26th 2009, 12:11 PM
  3. Polynomial division vs synthetic division
    Posted in the Algebra Forum
    Replies: 2
    Last Post: April 9th 2009, 06:49 AM
  4. Explanation Please
    Posted in the Math Topics Forum
    Replies: 1
    Last Post: April 1st 2009, 08:59 AM
  5. Help with an explanation
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: May 1st 2008, 03:00 AM

Search Tags


/mathhelpforum @mathhelpforum