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Math Help - How to simplify x^3 - y^3 / x - y

  1. #1
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    How to simplify x^3 - y^3 / x - y

    How to simplify

    x3 - y3 / x - y

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  2. #2
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    Re: How to simplify x^3 - y^3 / x - y

    Quote Originally Posted by AaPa View Post
    How to simplify

    x3 - y3 / x - y

    look up the factoring pattern for the difference of cubes in your text or online.
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  3. #3
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    Re: How to simplify x^3 - y^3 / x - y

    \frac{((x-y)(x^2+xy+y^2))}{(x-y)}
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    Re: How to simplify x^3 - y^3 / x - y

    You should know that:
    x^3 - y^3 = (x - y)(x^2 + xy + y^2)
    else you're not ready for this.

    And your expression needs brackets: (x^3 - y^3) / (x - y)
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  5. #5
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    Re: How to simplify x^3 - y^3 / x - y

    I knew that x^3 - y^3 = (x - y)(x^2 + xy + y^2)

    and

    x^3 - y^3 / (x - y) = (x^2 + xy + y^2)

    This is what I wanted to prove.
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  6. #6
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    Re: How to simplify x^3 - y^3 / x - y

    Quote Originally Posted by AaPa View Post
    I knew that x^3 - y^3 = (x - y)(x^2 + xy + y^2)
    and
    x^3 - y^3 / (x - y) = (x^2 + xy + y^2)
    This is what I wanted to prove.
    Once more, be CAREFUL with brackets; should be:
    (x^3 - y^3) / (x - y) = x^2 + xy + y^2

    There is NOTHING to prove: simply cancel out the (x - y) terms: see Dobby's post...
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  7. #7
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    Re: How to simplify x^3 - y^3 / x - y

    Is there a way to find these factors of
    x^3 - y^3
    except try and error?
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  8. #8
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    Re: How to simplify x^3 - y^3 / x - y

    Google "difference of cubes".
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