1/3x²y与-9yx²是不是同类项
x²-3xy-3x²y²+2yx²-y²x 合并同类项
7x²y-2xy²+2yx²+y²x-3xy²怎么做?是合并同类项在算
一道初一合并同类项题 2x²y-2y²x+2xy²+2yx²
3xy与-1/2yx是同类项吗
下列各组中的两项是不是同类项,为什么?①2a²b与2ab² ②3xy与-1/2yx③-2.1与3/4
-x^2y+5xy^2-yx^2合并同类项
合并同类项题目先化简,再求值2XY+3YX^2+6XY-6X^Y其中X=1/2 Y=-4
3xy+xy+2x²y+yx²+3x²y等于多少
合并同类项:6x^2y+2xy-3x^2y^2-7x-5yx-4y^2x^2-6x^2y
若|x-y+3|与|x+y-1999|互为相反数,求x+2yx−y
若|x-y+3|与|x+y-1999|互为相反数,求x+yx−y
x^3—2x^2y—y^2x+yx^2+2xy^2—y^3合并同类项