## Algebra: A Combined Approach (4th Edition)

$x^{6}$ + 1 = $x^{4}$ + $x^{2}$ $x^{6}$ - $x^{4}$ = $x^{2}$ - 1 $x^{4}$($x^{2}$ -1) = $x^{2}$ - 1 $x^{4}$ = 1 Thus, x is either 1 or -1