Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Who's Online (8)

Please review the site Rules, Terms of Service, and Privacy Policy at your convenience. Rules, TOS, Privacy
Get familiar with the reaction system: Introducing the Reaction System

Algebra gurus

   There is a short ish' way of working this but I can't remember what it was or even what this is called.   

Comments

  • Return of a 30yr bond held for 1 year. 
  • Other than the last term in your eqution, that has an F rather than a cF, it is a finite geometric sequence. Ignoring the last term, you can factor the cF out and get P1 = x + x^2 + ... + x^n; which equals P1 = x (1 - x^n) / (1 - x). (I'm using P1 rather than P since this is a solution to only part of your equation.) See, mathworld.wolfram.com/GeometricSeries.html where the formula is the second from the bottom, where I have used x rather than r.

     

    Using my notation, x = 1 / (1+r) and some tedious algebra shows P1 = (1 - 1/(1+r^n))/r which is similar to the first term in this equation:

    where they have used C instead of cF, i instead of r and M instead of F. See, www.investopedia.com/university/advancedbond/bond-pricing.asp 

    Note, in your equation if you are given any 3 of your variables you can theoretically solve for the 4th. While you can solve algebraically for c, F or P you cannot solve for r algebraically if n>3 (or at least I think that is the case) because it is a non-linear and non-quadratic equation. 

    Solving algebraically means writing down an equation such that r = .... 

    That doesn't mean you can't solve for r, it just means you can't write down a simple equation. If you plugged in values for P, C and F in Excel you can use the "goal seek" tool in the "what if analysis" option under Data to solve for r, since it is a non-linear numerical algorithm.

    Hope that helps a little.
  • That made my head hurt. 

    Found an online summation calculator that made life much easier.

    Thank you for the help.

    Working 7 days a week now.  Routine is work@4am, home@4pm, take dogs out (do not sit down or will fall asleep), shower, start on homework, wife gets home around 5pm and feeds me, bed around 9'ish -10'ish.

    Damn it Jr., wish I could quit work.              
Sign In or Register to comment.