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    Use set notation to describe the set of values of x for which:
    2x^2-x-1<0 and 14<3x-2
    Answer is meant to be 'NO Values'???
    But I solved.. X =-0.5 and 1 and 16/3
    Any help would be much appreciated
    I'm confused
    Thank you
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    (Original post by Musicanor)
    Use set notation to describe the set of values of x for which:
    2x^2-x-1<0 and 14<3x-2
    Answer is meant to be 'NO Values'???
    But I solved.. X =-0.5 and 1 and 16/3
    Any help would be much appreciated
    I'm confused
    Thank you
    Well neither of those two values satisfy the second inequality. Post your working if you'd like someone to check it.
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    You'll have to get a set of values that satisfy both inequalities. In your case the two you have mentioned above. You've already found out the values for 'X' to both equations; yet neither of them satisfy each other by not meeting certain conditions of being less or more some value for 'X' for each of them.

    For instance try to picture it on a number line and draw it out if you can...

    The first one is between the range '-0.5 < X < 1' where as the second one is 'X >16/3'

    Therefore by visualising these together on a single number line, you know there is no in-between area for then, hence there is no value for 'X' that satisfy both. Hope this makes more sense to you! Feel free to ask me again if I need to clarify anything else.
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    (Original post by Chocolate beaver)
    You'll have to get a set of values that satisfy both inequalities. In your case the two you have mentioned above. You've already found out the values for 'X' to both equations; yet neither of them satisfy each other by not meeting certain conditions of being less or more some value for 'X' for each of them.

    For instance try to picture it on a number line and draw it out if you can...

    The first one is between the range '-0.5 < X < 1' where as the second one is 'X >16/3'

    Therefore by visualising these together on a single number line, you know there is no in-between area for then, hence there is no value for 'X' that satisfy both. Hope this makes more sense to you! Feel free to ask me again if I need to clarify anything else.
    Thank you this was really helpful
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    (Original post by ghostwalker)
    Well neither of those two values satisfy the second inequality. Post your working if you'd like someone to check it.
    Thank you, this was really helpful
 
 
 
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