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    write down three values of x that satisfy the equation x(x-3)(2x+1)=0

    how do I do this?
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    (Original post by madfish)
    write down three values of x that satisfy the equation x(x-3)(2x+1)=0

    how do I do this?
    For the equation to equal zero, one of the three terms in the product must equal 0.
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    (Original post by joostan)
    For the equation to equal zero, one of the three terms in the product must equal 0.
    so x= 0, 3, -1/2?
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    (Original post by madfish)
    write down three values of x that satisfy the equation x(x-3)(2x+1)=0

    how do I do this?
    If

    a_1 \times a_2 \times a_3 \times ... \times a_n = 0

    then either the first, or the second, or the third..... or the nth term is zero.
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    (Original post by madfish)
    so x= 0, 3, -1/2?
    yes
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    (Original post by Indeterminate)
    If

    a_1 \times a_2 \times a_3 \times ... \times a_n = 0

    then either the first, or the second, or the third..... or the nth term is zero.
    OKay I got the values of x but how do I do the next bit,.? it says: hence solve the inequality x(x-3)(2x+1) > 0
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    (Original post by joostan)
    yes
    OKay I got the values of x but how do I do the next bit,.? it says: hence solve the inequality x(x-3)(2x+1) > 0
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    (Original post by joostan)
    yes
    OKay I got the values of x but how do I do the next bit,.? it says: hence solve the inequality x(x-3)(2x+1) > 0
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    (Original post by madfish)
    OKay I got the values of x but how do I do the next bit,.? it says: hence solve the inequality x(x-3)(2x+1) > 0
    For what values is the function greater than 0?
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    (Original post by Felix Felicis)
    For what values is the function greater than 0?
    x>3, x>-0.5 x<0
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    (Original post by madfish)
    x>3, x>-0.5 x<0
    yes
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    (Original post by Felix Felicis)
    yes
    how are you meant to do this?

    find a set of values of x for which both 6x-7<2x+3 and 2x^2-11x +5 >0
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    (Original post by madfish)
    how are you meant to do this?

    find a set of values of x for which both 6x-7<2x+3 and 2x^2-11x +5 >0
    remember for this kind of question always draw an inequality line.

    Work out x values for both equations first, then draw the inequality line for both equations and then you should see values of x which satisfiy both equations. (hope that makes sense)
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    Solve both inequalities and adjust the set of solutions accordingly
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    (Original post by gaffer dean)
    remember for this kind of question always draw an inequality line.

    Work out x values for both equations first, then draw the inequality line for both equations and then you should see values of x which satisfiy both equations. (hope that makes sense)
    Thanks lad! One thing.. What's an equality line?
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    (Original post by madfish)
    Thanks lad! One thing.. What's an equality line?
    see this: http://www.sparknotes.com/math/algeb...section4.rhtml
 
 
 
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