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    Sorry, quesion says:

    Fins p and q such that:

    f(x) = (x-3)(x^2 + px + q)

    Then factorise fully f(x)
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    (Original post by badmathkid)
    Sorry, quesion says:

    Fins p and q such that:

    f(x) = (x-3)(x^2 + px + q)

    Then factorise fully f(x)
    i don't understand tho, what is f(x) supposed to be equal to other than the expression you gave? cus you can use any old value for p and q

    in other words, post the full question please
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    (Original post by badmathkid)
    Sorry, quesion says:

    Fins p and q such that:

    f(x) = (x-3)(x^2 + px + q)

    Then factorise fully f(x)
    What's the full expression? There's not enough info in this post.
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    You should have a cubic that goes with this. Factorise the cubic by equating coefficients. You can then find p and q and factorise the quadratic. You should get something like f(x)=(x-3)(x+r)(x+s) if the quadratic can be factorised.
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    (Original post by JemmaSimmons)
    You should have a cubic that goes with this. Factorise the cubic by equating coefficients. You can then find p and q and factorise the quadratic. You should get something like f(x)=(x-3)(x+r)(x+s) if the quadratic can be factorised.
    Yes I just realised haha. I've worked it out now but the cubic was x^2 +3x-28. Took me forever! Thank you.
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    (Original post by badmathkid)
    Yes I just realised haha. I've worked it out now but the cubic was x^2 +3x-28. Took me forever! Thank you.
    No problem, congrats on cracking it!
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    (Original post by JemmaSimmons)
    No problem, congrats on cracking it!
    Thank you!
 
 
 
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