1
y`=-4x³+18x=-2x(x-3/√2)(x+3/√2)=0
x=0 x=3/√2 x=-3/√2
+ _ + _
-----------(-3/√2)-----------(0)-------------(3/√2)-----------
возр убыв возр убыв
2
{x+4>0⇒x>-4
{x+3>0⇒x>-3
{x>0
x∈(0;∞)
ln[(x+4)/(x+3)]≤lnx
(x+4)/(x+3)-x≤0
(x+4-x²-3x)/(x+3)≤0
(x²+2x-4)/(x+3)≥0
x²+2x-4=0
D=4+16=20
x1=(-2-2√5)/2=-1-√5
x2=-1+√5
x+3=0
x=-3
_ + _ +
------------(-1-√5)---------(-3)---------(-1+√5)-------------
-1-√5≤x<-3 U x≥-1+√5 U x>0
x∈[√5-1;∞)