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    2x^4+14x^2+24
    I got one solution but I don't know why the other solution is supposed to be 2(x^2+3) when I divided the equation by 2 at the beginning please help.Name:  image.jpg
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    I can't tell what the question is
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    (Original post by CorpusLuteum)
    I can't tell what the question is
    its at the top
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    (Original post by p29)
    its at the top
    Is the quadratic equal to zero.
    Are you only finding x? Why is there a Y.
    Be more clear.
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    (Original post by p29)
    2x^4+14x^2+24
    I got one solution but I don't know why the other solution is supposed to be 2(x^2+3) when I divided the equation by 2 at the beginning please help.
    As above, be more clear.

    Are you solving 2x^4+14x^2+24=0??? Or are you rearranging for something?

    You let y=x^2 got up to (y+3)(y+4)=0 which is almost correct.

    So y=-3 or y=-4

    Hence x^2=-3 or x^2=-4

    Which gives you complex roots.
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    (Original post by p29)
    its at the top
    You're overcomplicating it - the solution should only really be three lines max.
    Start with the equation, divide by 2, factorise it (as (x^2+a)(x^2+b) of course) and then solve. Just because the quadratic is in x^2 as opposed to x doesn't mean you can't solve it in the normal way.
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    (Original post by RDKGames)
    As above, be more clear.

    Are you solving 2x^4+14x^2+24=0??? Or are you rearranging for something?

    You got up to (y+3)(y+4)=0

    So y=-3 or y=-4

    Hence x^2=-3 or x^2=-4

    Which gives you complex roots.
    =0 and I have to factorise it
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    (Original post by p29)
    =0 and I have to factorise it
    If you have to factorise it then you've already done it with the y's, so replace them with x2 and you're done.
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    (Original post by p29)
    =0 and I have to factorise it
    the book says that when it is factorised one of them will be 2(x^2+3) which i dont understand
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    ????
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    is the book wrong?
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    Okay what factorisation have you got so far?
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    (Original post by p29)
    is the book wrong?
    No. You have factored out a 2 at the start so you need to bring it back.
 
 
 
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