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Homework Help: Integration proof

  1. Mar 28, 2010 #1
    1. The problem statement, all variables and given/known data

    prove or refute : let f(x), g(x) be integrable functions on [a,b] so |f(x)-g(x)| integrable on a [a,b]

    2. Relevant equations

    3. The attempt at a solution
    I'm pretty sure that it's right, I just can't find formal proof, someone can give me direction.
  2. jcsd
  3. Mar 30, 2010 #2
    Welcome Rony,
    Use the triangle inequality |f(x)-g(x)| <= |f|+|g| to prove finiteness & the fact that f-g can be approximated with the corresponding differences of step functions
    approximating f & g.
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