Question

quantas raízes possui x^(3 )+6x^(2)+5x-12=0 <=>(x-1).(x+3).(x+4)=0

Answer 1

$x^3+6x+5x-12=0$

$(x-1)\cdot(x+3)\cdot(x+4)=0$

$\bullet~~x-1=0~\longrightarrow~\boxed{x'=1}$

$\bullet~~x+3=0~\longrightarrow~\boxed{x"=-3}$

$\bullet~x+4=0~\longrightarrow~\boxed{x=-4}$

$\text{S}=\{-4,-3,1\}$

Logo, $x^3+6x^2+5x-12$ possui três raízes.