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    Could you show me how its done?

    x^3+x^2-6x ?

    Could you show the steps as well I got x(x+3)(x-2) however when check i expand i get something different.
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    (Original post by bobjon22444)

    I got x(x+3)(x-2).
    this is exactly right :yep:
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    I think the answer is x(x^2+x-6), this is because everything in the brackets is being multiplied by the outside. The common factor here is x and,

    x(x^2)=x^3

    x(x)=x^2

    x(-6)=-6x

    =x^3+x^2-6x
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    (Original post by Black Magic)
    I think the answer is x(x^2+x-6), this is because everything in the brackets is being multiplied by the outside. The common factor here is x and,

    x(x^2)=x^3

    x(x)=x^2

    x(-6)=-6x

    =x^3+x^2-6x
    ...it clearly says completely.

    How do you factorise the quadratic x^2 + x - 6?
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    (Original post by Zacken)
    ...it clearly says completely.

    How do you factorise the quadratic x^2 + x - 6?
    True. I am no maths expert but my answer is what I would do. I think you are probably correct.
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    (Original post by the bear)
    this is exactly right :yep:
    I know but when I expand to check I get x^4+6x-6... Is there a different way to check if you get factorising right?
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    (Original post by bobjon22444)
    Could you show me how its done?

    x^3+x^2-6x ?

    Could you show the steps as well I got x(x+3)(x-2) however when check i expand i get something different.
    (Original post by bobjon22444)
    I know but when I expand to check I get x^4+6x-6... Is there a different way to check if you get factorising right?

    x(x+3)(x-2) = x(x\times x - 2\times x + 3 \times x - 2 \times 3) = x(x^2 +x - 6) = x^3 + x^2 - 6x

    (Original post by Black Magic)
    True. I am no maths expert but my answer is what I would do. I think you are probably correct.
    Look up quadratic factorisation.
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    (Original post by Zacken)
    x(x+3)(x-2) = x(x\cdot x - 2\cdot x + 3 \cdot x - 2 \cdot 3) = x(x^2 +x - 6) = x^3 + x^2 - 6x



    Look up quadratic factorisation.
    Wait what are those dots ?
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    (Original post by bobjon22444)
    Wait what are those dots ?
    Multiplication, I'll edit it and use the times symbol instead.

    Edited: is that any better?
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    (Original post by bobjon22444)
    Wait what are those dots ?
    Do you know how to expand brackets

    (a+b)(c+d) = a(c+d) + b(c+d) = a \times c + a \times d + b \times c + b\times d
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    (Original post by bobjon22444)
    Could you show me how its done?

    x^3+x^2-6x ?

    Could you show the steps as well I got x(x+3)(x-2) however when check i expand i get something different.
    x(x^2+x-6)... Find the common factor
    x(x+3)(x-2)... Factorise the quadratic in the bracket.

    You've got the correct answer....


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    (Original post by Zacken)
    Do you know how to expand brackets

    (a+b)(c+d) = a(c+d) + b(c+d) = a \times c + a \times d + b \times c + b\times d
    I see thank you very much. Maths is starting to make a lot more sense.
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    (Original post by bobjon22444)
    I see thank you very much. Maths is starting to make a lot more sense.
    Great! Glad I could help. :-)
 
 
 
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