Упростите выражение (2x+y)(4x^2-2xy-x^2)-y^2(y-1)-7x^3. 1)x+3 2)y^2-x^3-3x^2 3)2xy-3x^2 4)4x^2+y^2
1.(2x+y)(4x^2-2xy-x^2)-y^2(y-1)-7x^3 = (2x+y)(3x^2-2xy)-y^3+y^2-7x^3 = 6x^3-4x^2y+3x^2y-2xy^2-y^3+y^2-7x^3 = -x^3-x^2y-2xy^2-y^3+y^2