1
x-1>0⇒x>1
x-1<8⇒x<9<br>x∈(1;9)
x=8 наиб
2
x²-x-2>0
x1+x2=1 u x18x2=-2⇒x1=-1 u x2=2
x<-1 U x>2
x²-x-2≤4
x²-x-6≤0
x1=x2=1 U x1*x2=-6⇒x1=-2 U x2=3
-2≤x≤3
x∈[-2;-1) U (2;3]
x={-2;3}-2 целых
3
x+4>0⇒x>-4
7-x>0⇒x<7<br>x+4<18/(7-x)<br>(x+4)-18/(7-x)<0<br>(7x+28-x²-4x-18)/(7-x)<0<br>(x²-3x-10)/(x-7)<0<br>x²-3x-10=0
x1+x2=3 U x1*x2=-10⇒x=-2 u x2=5
x-7=0⇒x=7
_ + _ +
------------(-2)--------(5)-------------(7)------------
x∈(-4;-2) U (5;7)
x={-3;6}
-3+6=3-сумма целых