Question

số nguyên x thỏa mãn : (x+2)(x+4)<0

Answer 1

(x+2)(x + 4) < 0 

\(\int^{x+2>0}_{x+4<0}\Rightarrow\int^{x>-2}_{x<-4}\Rightarrow x<-4;x>-2\) (vô lí)

\(\int^{x+2<0}_{x+4>0}\Rightarrow\int^{x<-2}_{x>-4}\Leftrightarrow x<-2;x>-4\Rightarrow x=-3\)

Vậy x =-3 

Answer 2

Ta co : (x+2)(x+4)=0

th1 : x+2=0=>x=0+2=2​

​th2 : x+4=0=>x=0+4=4

​Vay x=2 hoac 4 **** nho