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Math Help - Factoring

  1. #1
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    Factoring

    Factor:

    x^3+4

    ?
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  2. #2
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    Sum of cubes:

    a^{3} + b^{3} = (a + b)\left(a^{2} - ab + b^{2}\right)
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  3. #3
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    Ok. So what would be the answer? Would (x+4)(x^2-4x+16) be correct ?
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  4. #4
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    Not quite. Notice how 4 represents b^{3}. If that's the case, what is b?
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  5. #5
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    Question

    I don't get it. :/
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  6. #6
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    b seems to be 4 to me.
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  7. #7
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    This is what I'm saying:
    b^{3} = 4

    Solve for b.

    If b = 4, then b^{3} = 64 \neq 4
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  8. #8
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    but b^{3} = 64 does equal 4.

    Can you please fully explain the problem out to me. I foiled my answer 5 times and every time I got x^3+64
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  9. #9
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    Oh! I see where I messed up. What I needed factored was x^3+64 not x^3+4 which I posted. I'm really sorry.
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  10. #10
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    In that case, your original answer was right.
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  11. #11
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    Thank you. Sorry again for the confusion.
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