## Algebra and Trigonometry 10th Edition

$+1, -1 , \sqrt3, -\sqrt3$
$x^4-4x^2+3=0$ $(x^2-3)(x^2-1)=0$ $x^2-1=(x-1)(x+1)=0$ gives x=1 or -1 $x^2-3=(x-\sqrt3)(x+\sqrt3)=0$ gives $x= \sqrt3$ or $-\sqrt3$