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: Componendo and Dividendo

  1. Oct 13, 2011 #1
    Please solve this equation :

    x3+3x/3x2+1 = 341/91

    I applied Componendo and Dividendo, then k-method but could not solve this question. Please help me.
  2. jcsd
  3. Oct 13, 2011 #2


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper
    Gold Member

    Do you mean: (x3+3x)/(3x2+1) = 341/91 ?

    Parentheses are important.
  4. Oct 13, 2011 #3
  5. Oct 13, 2011 #4


    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Did you try applying the rules of algebra?
  6. Oct 13, 2011 #5
    no, i must use either componendo and dividendo or k-method. No algebra at all.
  7. Oct 13, 2011 #6


    Staff: Mentor

    I doubt that many of us here even know what "componendo and dividendo" mean or what "k-method" means.

    The first two are apparently Spanish or maybe Portuguese for combining and dividing.
  8. Oct 13, 2011 #7


    User Avatar
    Homework Helper
    Education Advisor
    Gold Member

    physics kiddy,
    Are you trying to solve for x, or are you substituting a value for x in order to evaluate the rational expression?
  9. Oct 13, 2011 #8
    Hiii physics kiddy !

    Try applying componendo and dividendo once more. I will guide you. :wink:

    k-method cannot work here because there are no proportional relation given.
    If there are relations like a,b,c and d are in continued proportion , then k-method can be applied.

    You can even try cross-multiplying.
  10. Oct 13, 2011 #9
    Please solve this question. I am tired of using componendo and dividendo but all my efforts go useless. I can't go any further. It would be very kind of you if you solve the question. Thanks again for the help.
  11. Oct 13, 2011 #10


    User Avatar
    Homework Helper

    You need to show an attempt at the problem. Show us what you've tried.
  12. Oct 13, 2011 #11


    User Avatar
    Science Advisor

    We don't dislike you enough to want to prevent you from learning! I am closing this thread. If you really want help, start a new thread showing what you have done.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook