# higher power equation!

• April 13th 2012, 01:43 AM
lawochekel
higher power equation!
pls somebody have to help me on the best way to simplify equations like these;

$x^3-1 , x^4-1$

thanks
• April 13th 2012, 01:52 AM
biffboy
Re: higher power equation!
They are expressions not equations.
x^3-1 = (x-1)(x^2+x+1)

x^4-1 = (x^2-1)(x^2+1) = (x-1)(x+1)(x^2+1)
• April 13th 2012, 01:57 AM
princeps
Re: higher power equation!
Quote:

Originally Posted by lawochekel
pls somebody have to help me on the best way to simplify equations like these;

$x^3-1 , x^4-1$

thanks

$x^n-1 =\begin{cases}\left(x^{n/2}-1\right)\left(x^{n/2}+1\right), & \text{if }n\text{ is even} \\(x-1)\cdot \displaystyle \sum_{i=0}^{n-1} x^i, & \text{if }n\text{ is odd}\end{cases}$