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Math Help - Factoring sum of two cube

  1. #1
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    Factoring sum of two cube

    can you please help me understand this kind of problem?

    factor sum of two cube:
    27x+3x^3



    can you explain me by steps? thank you!
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  2. #2
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    Quote Originally Posted by Anemori View Post
    can you please help me understand this kind of problem?

    factor sum of two cube:
    27x+3x^3



    can you explain me by steps? thank you!
    27x+3x^3

    This isn't the sum of two cubes. Although 27 is a cube, 27x is not a cube. Also, 3x^3 isn't a cube either.

    You can factor out 3x to obtain:

    x(27+3x^2)=3x(9+x^2)
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  3. #3
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    (a^3+b^3)=(a+b)(a^2-ab+b^2)

    But this will not work for your expression as said above.
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