Question

          resolva no universo dos numeros complexos as equaçoes  a)x²+4=0     b)x²+121=0 

Answer 1

a)

$x^{2} +4=0$
$x^{2} =-4$
$x= \sqrt{-4}$
$x=2i$

b)
$x^{2} +121=0$
$x^{2} =-121$
$x= \sqrt{-121}$
$x=11i$

Beleza..