Question

Resolva em C a equação (x2+9)x(x2-1)=0

Answer 1

Fator I:

$x^2+9=0\\x^2=-9\\x^2=9\cdot(-1)\\x^2=9\cdot\,i^2\\x^2=9i^2\\x=\pm3i$

Fator II:

$x=0$

Fator III:

$x^2-1=0\\x^2=1\\x=\pm1$
 
 Logo, $\boxed{S=\left\{\pm3i,0,\pm1\right \}}$.