M Math wiz ya rite 09 Junior Member Joined Aug 27, 2006 Messages 136 Nov 16, 2006 #1 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

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 Super Moderator Staff member Joined Feb 4, 2004 Messages 15,943 Nov 16, 2006 #2 1) Difference of squares. Apply the formula. 2) Take the two common factors out front, and simplify what remains. Eliz.

1) Difference of squares. Apply the formula. 2) Take the two common factors out front, and simplify what remains. Eliz.

G galactus Super Moderator Staff member Joined Sep 28, 2005 Messages 7,216 Nov 16, 2006 #3 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) \(\displaystyle x^{8} - 1\) Click to expand... Difference of squares: \(\displaystyle \L\\x^{8}-1=\underbrace{(x^{4})^{2}-(1)^{2}}_{(x^{4}+1)\underbrace{((x^{2})^{2}-(1)^{2})}_{\text{(x^{2}+1)}\underbrace{\text{(x^{2}-1)}}_{\text{(x+1)(x-1)}}\) \(\displaystyle \L\\(x^{4}+1)(x^{2}+1)(x+1)(x-1)\)

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) \(\displaystyle x^{8} - 1\) Click to expand... Difference of squares: \(\displaystyle \L\\x^{8}-1=\underbrace{(x^{4})^{2}-(1)^{2}}_{(x^{4}+1)\underbrace{((x^{2})^{2}-(1)^{2})}_{\text{(x^{2}+1)}\underbrace{\text{(x^{2}-1)}}_{\text{(x+1)(x-1)}}\) \(\displaystyle \L\\(x^{4}+1)(x^{2}+1)(x+1)(x-1)\)