1
1)y²/(x-2y)(x+2y):1/[2(x+2y)]=y²/(x-2y)(x+2y) * 2(x+2y)=2y²/(x-2y)
2)xy/(x-2y)-2y²/(x-2y)=(xy-2y²)/(x-2y)=y(x-2y)/(x-2y)=y
2
3x²-13x_4=0
D=169-48=121
x1=(13-11)/6=1/3
x2=(13+11)/6=4
3
-5x-9>39x+3-35x+25
-5x-4x>28+9
-9x>37
x<-4 1/9<br>x∈(-∞;-4 1/9)
4
1/3*√360-√5*(√20+√8)=1/3*6√10-√100-√40=2√10-10-2√10=-10