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[A-Level Quadratics/Inequalities] Use you graph to solve the inequality 2𝑥^3 −7𝑥^2 watch

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    So I have the graph of this: 2𝑥3 −7𝑥2 −7𝑥 +12 < 0


    But I have no idea what it's asking me to do? I guess I missed that lesson. Can anyone help?
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    (Original post by WannabeCrypto)
    So I have the graph of this: 2𝑥3 −7𝑥2 −7𝑥 +12 < 0


    But I have no idea what it's asking me to do? I guess I missed that lesson. Can anyone help?
    So the solutions to the inequality are the x values where the graph of the curve is below the x axis.
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    Start by factorising.
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    (Original post by B_9710)
    So the solutions to the inequality are the x values where the graph of the curve is below the x axis.
    And this is written how?
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    (Original post by WannabeCrypto)
    And this is written how?
    (x+a)(x+b)(x+c) &lt; 0
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    (Original post by WannabeCrypto)
    And this is written how?
    Usually as inequalities so the curve will be below the x axis say between a and b so we will write  a&lt;x&lt;b and this solves the inequality but there can be many regions where the inequality is satisfied.
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    Firstly start of by using the factor therom which is when you sub in values into x to make the equation equal to zero.
    Then, using long division, divide the factor by the equation in the question.
    The answer you get from that can be factorized to find the values of x.
    Draw and plot them on a graph and write down the inequality.

    If you need more help in explaining the steps then let me know and I can try and explain in in more depth.
 
 
 

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