need help with my factoring probelms

Math wiz ya rite 09

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Aug 27, 2006
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i had a bulk of factoring problems for hw tonight and was doing fine until the very last two which I couldn't get. Please help....

1) x^8 - 1

2) (x - 3)^2 * (x + 5) + (x - 3)(x + 5)^2
 

stapel

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1) Difference of squares. Apply the formula.

2) Take the two common factors out front, and simplify what remains.

Eliz.
 

galactus

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Math wiz ya rite 09 said:
i had a bulk of factoring problems for hw tonight and was doing fine until the very last two which I couldn't get. Please help....

1) \(\displaystyle x^{8} - 1\)
Difference of squares:

\(\displaystyle \L\\x^{8}-1=\underbrace{(x^{4})^{2}-(1)^{2}}_{(x^{4}+1)\underbrace{((x^{2})^{2}-(1)^{2})}_{\text{(x^{2}+1)}\underbrace{\text{(x^{2}-1)}}_{\text{(x+1)(x-1)}}\)

\(\displaystyle \L\\(x^{4}+1)(x^{2}+1)(x+1)(x-1)\)
 
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