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Help with inequation question: 1/x-2<1 please?

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Why is the answer x<2 and x>3 and why isn't it 2<x<3?

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  1. hi,

    1/x-2 &lt; 1

    =&gt; 1/x &lt; 1+2

    =&gt; 1/x &lt; 3

    =&gt; x &gt; 1/3

    this is your required answer. Hope this helps. Bye.


  2. 1/x-2&lt;1

    +2      +2

    1/x&lt;3

    Therefore x&lt;3

  3. I assume you mean 1/(x-2)&lt;1   right?

    You have to solve a simpler equation first:

    Replace

    x - 2 --&gt; x

    1 / x &lt; 1

    The answer to this is, of course  x &gt; 1

    Then you solve:

    x - 2 &gt; 1

    Which is x &gt; 3

    If the question really is 1/x-2&lt;1

    Tha simplifies to 1/x &lt; 3

    which is

    x &lt; (1/3)  or   x &lt; 0.3333

  4. Assuming the inequation is 1/(x-2) &lt; 1.

    When multiplying both sides of an inequation, you must reverse the inequation sign when the multiplying number is negative.

    For example, multiplying the inequation &quot;a &lt; b&quot; with the number -1 gives you the inequation &quot;-a &gt; -b&quot;.

    In the inequation 1/(x-2) &lt; 1 we multiply both side with (x-2). However it is tricky because we have to distinguish 2 cases.

    1) When (x-2) &gt; 0 (which means x &gt; 2)

       the inequation becomes 1&lt;x-2, and then x&gt;3

       As a result, the inequation is true for any x &gt; 3

      

    2)  When (x-2) &lt; 0 (which means x &lt; 2)

       the inequation becomes 1&gt;x-2, and then x&lt;3

       As a result, the inequation is true for any x &lt; 2

    The final answer is &quot;x&lt;2 or x&gt;3&quot;

  5. 1/(x-2) &lt; 1

    If x-2 &gt; 0

    Cross multiply to get:

    1 &lt; x - 2

    3 &lt; x

    x &gt; 3

    Check this with the assumption:

    3-2 &gt; 0 is true

    This is one part of a valid answer.

    If x-2 &lt; 0:

    Cross multiply to get:

    1 &gt; x - 2 ------ multiplying both sides by a negative value willl reverse the inquality.

    3 &gt; x

    x &lt; 3

    But the assumption limits this to the values such that x&lt;2

    x &lt; 2

    x ∈ {(-∞,2) U (3,∞)}

  6. Easy. Treat it as an equation and:-

    1/(x-2) &lt; 1       multiply bs by (x - 2)  (bs = both sides)

    1 &lt; x - 2      Add 2 to bs

    3 &lt; x     ie   x &gt; 3

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