Results 1 to 2 of 2

Math Help - another comparison thereom problem

  1. #1
    Member
    Joined
    Feb 2009
    Posts
    91

    another comparison thereom problem

    Hi

    I am suppose to use the comparison thereom to determine if the following integral is convergent or divergent

    integral sign (S) a= e and b= infinity (2010 + cos 2011 x)/ 2009x dx

    these numbers are huge and I don't know where to start - especially with a cos in the middle of it.

    Help!

    Calculus beginner
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Senior Member
    Joined
    Apr 2009
    From
    Atlanta, GA
    Posts
    409
    I=\int_0^\infty \frac{2010+\cos(2011x)}{2009x}dx

    The range for cosine is [-1,1], so the numerator N\in[2009,2011]. The entire fraction f(x)\in[\frac{1.001}x,\frac1x].

    So, since f(x)>\frac{1.001}x, I>\int_0^\infty\frac{1.001}{x}dx. Can you get it from here?
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Comparison or Limit Comparison Test Problem
    Posted in the Calculus Forum
    Replies: 2
    Last Post: March 12th 2010, 08:46 AM
  2. Limit comparison/comparison test series
    Posted in the Calculus Forum
    Replies: 2
    Last Post: March 25th 2009, 09:27 PM
  3. Comparison & Limit Comparison test for series
    Posted in the Calculus Forum
    Replies: 4
    Last Post: March 25th 2009, 05:00 PM
  4. Mean Value Thereom
    Posted in the Calculus Forum
    Replies: 5
    Last Post: February 5th 2008, 02:59 PM
  5. DeMoivre's Thereom
    Posted in the Algebra Forum
    Replies: 3
    Last Post: January 18th 2008, 05:30 PM

Search Tags


/mathhelpforum @mathhelpforum