1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Partial Fractions, Irreducible quadratic factors

  1. Oct 26, 2007 #1
    Arc Length, Irreducible quadratic factors

    i'm having a hard time seeing this method, and i have to use this method on one of the problems i'm doing to find it's Arc Length.


    the book suggests to first divide then use a u-substitution. i know that when the power in the numerator is greater than the denominator, i can perform long-division, but i don't see how i can divide this.
    Last edited: Oct 26, 2007
  2. jcsd
  3. Oct 26, 2007 #2
    i dont know whether i am gettin u well, but you could do this inegral by doing this to the function under the integral sign

    v^2/(v^2-) =(v^2-1+1)/(v^2-1) = (1- 1/(v-1)(v+1) )

    then you could use partial fraction by letting

    1/(v-1)(v+1) = A/(v-1) + B /(v+1), and then finding the values of B and A. Pardone me if i misunderstood u.
  4. Oct 26, 2007 #3

    Gib Z

    User Avatar
    Homework Helper

    Well, like sutupidmath did, add one and then subtract one to the numerator. Then, instead of factoring the new denominator and partial fractions-ing, Try a hyperbolic substitution, I think you will find it quicker.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook