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Help, need to get down absolute value equations and inequalities.

  1. Oct 20, 2008 #1
    I'm taking an algebra & triginometry class at my college and my professor is kind of slow and unclear. I think I'm a fast learner and a good understander which is why I came here to get this info down. We're up to complex fractions or radical equations right now I think, forgot which. Something about square roots also...but that's not the point.

    We did that absolute value equation and inequality equation stuff a while ago. I have no idea how to do absolute value equations and I forgot the open and closed dot stuff and the signs changing in solving inequalities. There's going to be a test on Thursday and I have Mondays off anyway so I've been studying the book and looking everything up on google to keep myself current with everything I've learned recently because it is REALLY easy to forget and I don't want to fail that test...The reason I'm asking about this even though we did it a while ago is just in case it comes up, it's good to have it down anyway because who knows about the final soon in December.

    Thanks a lot guys, I'm going to get some sample questions/problems we/I did and post them here and ask or see if I can or did do them right and learn.
  2. jcsd
  3. Oct 20, 2008 #2


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    Each absolute value expression contains an expression which can be of two possible conditions: It can be negative, or it can be positive-or-zero. You want to perform the evaluations based on each of the separate conditions.

    For inequalities, you want to first establish the critical points (and use a number line to help yourself see the solution which you are forming). The critical points are the values for which if your inequality were converted to an equality, the points would satisfy the equality.

    The critical points help to establish different parts of the number line which you can then test in your original relation (inequalities or absolute value equations). A point in a part of the line either does or does not satisfy the original relation.

    Further, you can find sensible enough instruction from most any good PreCalculus or College Algebra textbook. No need to find an internet source. I found good guidance on this stuff in a Larson, Hostetler, Edwards book; also in an older book by Nash, or Marsh? (not sure of the "older" book who wrote it).
    Last edited: Oct 20, 2008
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