Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Simplify the expression (need hint)

  1. Oct 13, 2012 #1
    Well, this is a task for those who prepares to enter a university.
    According to the textbook this task is among the easiest ones.

    I managed to simplify this part of the (4b^4 + 4ab^2+a^2):(2b^2 + a) = 2b^2 + a.

    Well, I can't proceed any further.

    Could you give me a hint?
     

    Attached Files:

  2. jcsd
  3. Oct 13, 2012 #2

    haruspex

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    Can you factorise the term on the right? Having factorised it, that gives you two 'roots', i.e. Relationships between a and b that would make that term vanish. Try substituting those, in turn, in denominators elsewhere to see if there's some cancellation. Likewise, the case 2a=b looks interesting. See what other terms vanish for that combination.
     
  4. Oct 13, 2012 #3
    You have to convert the upper fractions to a common denominator. Then you'll find that the numerator cancels out with part of the denominator. You'll get (I hope :smile:)
    [itex]\frac{b^2+b+ab+a}{b^2-ab-2a^2}[/itex].
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook