Math

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Ok heres another factoring that I need someone to check

Problem: -x^3 + 27

-(x^3 - 3^3)

So I moved the positive and found out what cubed would make 27

Using the forumla: (a-b)(a^2+ab+b^2)

-(x-3) (x^2 + 3x + 9)

Right? Or did I make a mistake?

  • Math -

    That is correct, you can always double check your answer by expanding it

    -(x^3+3x^2+9x-3x^2-9x-27)

    cancel the ones you need to cancel and you get
    -(x^3-27)
    =-x^3+27

  • Math -

    So I factored it right? Ha thanks alot.

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