Question

( 4x ) / ( x + 3 ) > x + 1

Answer 1

4x/(x+3)-(x+1)>0
(4x-x²-x-3x-3)/(x+3)>0
(x²+3)/(x+3)<0
x²+3>0 при любом х⇒x+3<0⇒x<-3
x∈(-∞;-3)