-0,3x^2(2y^2-x^2-5xy)=0,4c^2d(-4c^2-cd-d)=-6y(-7y^2+7)-y(-4y^2+5)=
1) y2-5xy-3x2/2y2+xy+2x2
-3y2x2 + 2y2 - 8yx + 4x2
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2