化简:x^3-x^2y+xy^2+yx^2+y^2x+y^3
已知x-y=4xy,则2x+3xy-2yx-2xy-y
3xy+xy+2x²y+yx²+3x²y等于多少
3x^2y-3xy^2+6yx^2-9y^2x
实数x、y、z满足x=6-3yx+3y-2xy+2z
已知y=3xy+x,求代数式2x+3xy−2yx−2xy−y
合并同类项:6x^2y+2xy-3x^2y^2-7x-5yx-4y^2x^2-6x^2y
x²-3xy-3x²y²+2yx²-y²x 合并同类项
-x^2y+5xy^2-yx^2合并同类项
若|x-y+3|与|x+y-1999|互为相反数,求x+2yx−y
已知x-3y=0,求2x+yx
6x²y+2xy-3x²y²-7x-5yx-4y²x²-6x²
求6x²y+2xy-3x²y²-7x-5yx-4y²x²-6x