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    It looks simple enough but i don't understand why you can't just multiply out the denominator so it ends up x^2 - y^2....

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    it makes no sense your mulipication :P
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    (Original post by FlamingSpittoon)
    It looks simple enough but i don't understand why you can't just multiply out the denominator so it ends up x^2 - y^2....

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    You cant multiply like that.
    Remember how you multiply our brackets.

    (x-y)^2 means (x-y)(x-y)
    Now multiply out using FOIL method.
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    (Original post by Aniaa)
    it makes no sense your mulipication :P
    I thought if something was (x-y)^2 it multiplied out as (x-y)(x+y)... ?
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    (Original post by FlamingSpittoon)
    I thought if something was (x-y)^2 it multiplied out as (x-y)(x+y)... ?
    No, squaring means (by definiton) multiplying something by itself. x^2 is x*x so (x-y)^2 is (x-y)*(x-y).

    I tihnk you may be getting confused with teh difference of 2 squares, it is true that x^2-y^2=(x-y)(x+y) but this is not what you are given here.
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    (Original post by MrHappyChappy)
    You cant multiply like that.
    Remember how you multiply our brackets.

    (x-y)^2 means (x-y)(x-y)
    Now multiply out using FOIL method.
    what is the FOIL method?
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    (Original post by james22)
    No, squaring means (by definiton) multiplying something by itself. x^2 is x*x so (x-y)^2 is (x-y)*(x-y).

    I tihnk you may be getting confused with teh difference of 2 squares, it is true that x^2-y^2=(x-y)(x+y) but this is not what you are given here.
    ahh okay, thanks.
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    (Original post by Secretnerd123)
    what is the FOIL method?

    A Method used to multiply out brackets.

    Firsts
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    FOIL
 
 
 
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