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Algebraic expressions - simplifying

  1. Apr 21, 2008 #1
    Hi all,

    I'm retaking the GRE soon and I keep making stupid algebra mistakes in my calculus problems so I'm going through a textbook from 1965 that is helpful but has me stumped on some problems. I hope someone can steer me in the right direction.

    1/(a-b)(a-c) + 1/(c-a)(c-b) + 1/(b-a)(b-c)

    Is there a way to simplify this? If I start multiplying out everything to get the LCD my final answer will be huge. Thanks in advance
     
  2. jcsd
  3. Apr 22, 2008 #2
    It shouldn't be too terrible. The obvious thing to note is that (b - a) = -(a - b), for example.
     
  4. Apr 22, 2008 #3

    HallsofIvy

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    Write everything with a denominator of (a-b)(a-c)(b-c) and add the fractions.
     
  5. Apr 22, 2008 #4

    mathwonk

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    basic advice: do not fear to write something down, just because you think it will be large and unmanageable. you have to plunge in without fear of what will come out. you have to get your hands dirty.
     
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