1)6/(y-3)(y+3) -1/(y-3)=(6-y-3)/(y+3)(y-3)=-(y+3)/(y+3)(y-3)=-1/(y-3)
2)-1/(y-3)*(y+3)²/5=-(y+3)²/5(y-3)=(y+5)/5(3-y)
2х^3+4х^2=8(x+2)
х^2(2х+4)=8(х+2)
Х^2(2(х+2))=8(х+2)
Х^2(2(х+2))/(х+2)=8
Х^2*2=8
X*2=4
X=2; -2
12х^2-3/18x+9=3(2x-1)(2x+1)/9(2x+1)=(2x-1)/3
3/8; 0,4; 2/3
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