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Homework Help: Proving an inequality

  1. Jul 20, 2010 #1
    1. The problem statement, all variables and given/known data

    Prove that if b is a positive number, such that a < b, then
    a/b<(a+1)/(b+1)

    2. The attempt at a solution

    I have tried a few things, attempting to prove it using the real line, and a bunch of other methods but have had no success. I Would greatly appreciate it if u can at least get me started.
     
  2. jcsd
  3. Jul 20, 2010 #2

    Dick

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    Clear out the fractions, i.e. multiply both sides by the common denominator. You didn't try that?
     
  4. Jul 20, 2010 #3
    I did before, but I made the most retarded mistake of thinking a(b+1)=b(a+1). Sorry about that. Thanx
     
  5. Jul 20, 2010 #4

    ehild

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    a<b. You can add any number to both sides of an inequality, it stays valid. Why not trying to add ab?

    ehild
     
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