Question

Срочно помогите 20 баллов даю,очень срочно надо х2 +2х < 8​

Answer 1

$x^2+2x<8\\x^2+2x-8<0\\x^2+4x-2x-8<0\\x(x+4)-2(x+4)<0\\(x+4)(x-2)<0\\\left \{ {{x+4<0} \atop {x-2>0}} \right. \to \left \{ {{x+4>0} \atop {x-2<0}} \right. \\\left \{ {{x<-4} \atop {x>2}} \right. \left \{ {{x>-4} \atop {x<2}} \right. \\x \in \varnothing\\x \in (-2;2)$