Question

Ache as raízes de 
y = x^4 - 6x^2 +9 

Answer 1

$x^4 - 6x^2 +9=0\\ \\ \boxed{y=x^2}\\ \\ y^2-6y+9=0\\ \\ \Delta=(-6)^2-4.1.9=36-36=0\\ \\ y=\frac{6}{2}=3\\ \\ x^2=3\\ \\ \boxed{x=\pm\sqrt3}$