(x^2-2xy+y^2)-(x^2+2xy+y^2)=

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/05/16 23:42:43

(x^2-2xy+y^2)-(x^2+2xy+y^2)=(x-y)^2-(x+y)^2
=((x-y)+(x+y))((x-y)-(x+y))
=(2x)(-2y)
=-4xy
再问：写出下列多项式的项数,次数,常数项:(1),a^2-a^2b+b^2+4/5 (2)x^2-2xy+y^2(3)x^2-2/3xy^2-1/2+y^2

（xy-x^2)乘以(xy)/(x-y) （x^2+xy/x-y)/（xy/x-y)计算 (x+y-2xy)(x+y-2)+(1-xy)² （-3x^y+2xy)-( )=4x^+xy (x^2-xy)y÷y-x/xy怎么做? (x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y) 已知x-y=4xy，则2x+3xy-2yx-2xy-y X²+2xy+y²/xy乘x²-2xy+y²/xy+y²= 已知x-xy=8,xy-y=-9,求x+y-2xy的值由已知x+y=-2,xy=3那么2(x+xy)-[(xy-3y)-x]-(-xy)等于多少? x-y/x²÷x²-2xy+y²/xy*（xy-x²） x^2+xy+x=36,y^2+xy+y=20,求x+y.