<em>№1</em>
2xy(2x^2-5xy+y^2)=4x^3y-10x^2y^2+2xy^3
<em>№2</em>
1,4x(0,5x-0,3y)-5(0,4y^2-4xy)+0,2y(8y-5x)=0,7 х^2+0,42ху-2у+20ху+1,6у-х=0,7х^2+20,42ху-0,4у-х
ОДЗ x>0
(log²(2)x-4log(2)x+4)/(6-x)>0
(log(2)x-2)²/(6-x)>0
(log(2)x-2)²>0 U 6-x>0
log(2)x=2⇒x=4
x<4 U x>4
6-x>0⇒x<6
x∈(0;4) U (4;6)
1+2+3+5=11