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A tough inequality question! watch

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    find x which allows this inequality to hold:
    1+2x-x^2>2/x

    So I thought since, we don't know if x is negative or positive create 2 cases. Case 1) where x is negative and therefore x+2x^2-x^3<2, and solve
    or case 2) where x is positive and therefore x+2x^2-x^3>2

    Then working out the solutions to each and finding which set of x values satisfy the equation?

    If you can't help me with the actual equation, please let me know if my idea seems sensible or if it is flawed. Thanks!
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    (Original post by Student10011)
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    Your thinking in fine.

    The cubic has easy roots.
 
 
 
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Updated: October 7, 2013

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