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Homework Help: Inequalities questions

  1. Mar 15, 2010 #1
    1. The problem statement, all variables and given/known data


    (1) Express the inequalities x≤3 and 1 ≤ x < 4 in interval notation.


    (2) Express in term of inequality: The distance between x and -3 is at least 5.




    3. The attempt at a solution

    (1) i don't know what he asking for ,,, can you explain it for me please

    (2) is it " x+(-3)≥5 " ,,,, x≥2 ? right ?

    in (2) he want me to find x or what is the story ?
     
    Last edited: Mar 15, 2010
  2. jcsd
  3. Mar 15, 2010 #2

    Mark44

    Staff: Mentor

    1. Look in your book for some examples of interval notation.
    2. Absolute values are used to represent distance.
     
  4. Mar 15, 2010 #3
    first one ... done ,,,

    2.
    it's gone be " abs (x-3) ≥ 5 " then solve for it ?
     
  5. Mar 15, 2010 #4

    Mark44

    Staff: Mentor

    From you problem description, all that is asked for is the expression. You don't need to solve the inequality.

    Your expression represents the distance between x and + 3.

    Also, there's a key on the keyboard that you can use for absolute values - |
     
  6. Mar 15, 2010 #5
    O,O ... how is that ? in the question it's -3 ,,, why in absolute i make it |x+3|≥ 5 ?
     
  7. Mar 15, 2010 #6

    Mark44

    Staff: Mentor

    To find the distance, you subtract, so the distance from x to -3 is represented as is x - (-3).
     
  8. Mar 15, 2010 #7
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