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    So basically I learnt a particular method of solving quad equations that my textbook doesn't use, so when I solve quadratic inequalities I get different critical values than the textbook? (Same numbers, different signs)

    Are these two expressions the same?:
    -3 < x < 1/3 (textbook)
    3 > x > -1/3 (my answer)

    The original inequality is 3x^2 + 8x - 3 < 0 if that makes a difference








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    No they are different, once u have factorised it try drawing the lines (in this case y = 3x -1 and y = x + 3) and see for what x values will this inequality be negative.

    Once the graph has been drawn you will be able to see that it's between -3 and 1/3
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    (Original post by hi-zen-berg)
    So basically I learnt a particular method of solving quad equations that my textbook doesn't use, so when I solve quadratic inequalities I get different critical values than the textbook? (Same numbers, different signs)

    Are these two expressions the same?:
    -3 < x < 1/3 (textbook)
    3 > x > -1/3 (my answer)

    The original inequality is 3x^2 + 8x - 3 < 0 if that makes a difference

    Posted from TSR Mobile
    How could they be the same
    As an example x=1 is included in your answer and excluded by the actual answer
    And, of course 3+8-3 = 8 which is not <0

    What was your factorisation?
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    (Original post by MaloneJ)
    No they are different, once u have factorised it try drawing the lines (in this case y = 3x -1 and y = x + 3) and see for what x values will this inequality be negative.

    Once the graph has been drawn you will be able to see that it's between -3 and 1/3
    (Original post by TenOfThem)
    How could they be the same
    As an example x=1 is included in your answer and excluded by the actual answer
    And, of course 3+8-3 = 8 which is not <0

    What was your factorisation?
    Ok thanks I reviewed it and I made a stupid mistake with signs, thanks


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