木块从粗糙的斜面顶端:X^4 +11x^2y^2 +y^2

(x+y)2-4(x+y-1) X^4 +11x^2y^2 +y^2 1/4(x+y)+1/2(x+y)*(x+y)>=x*根号y+y*根号x （x-y)^3*(x-y)^2*(y-x) 3X(X-Y)+2Y(X-Y) (x+y)^2+x+y 怎么因式分解 (x-y)^2×(y-x)^3=??? 已知X+Y=-4，求1/2（X+Y)+4(X-Y)-3(X-Y)-3/2(X+Y)-X+Y 2y-3x-9x^2+4y^2 x^4+x^2y^2+y^4 (因式分解）