(y-3)(y2+9)(y+3)-(2y2-y)2-19 упростить

(y-3)(y^2+9)(y+3)-(2y^2-y)^2-19=(y^3+9y−3y^2−27)(y+3)−4y^4+4y^3−y^2−19=y^4+3y^3+9y^2+27y−3y^3−9y^2−27y−81−4y^4+4y^3−y^2−19=−3y^4+4y^3−y^2−100