(x-y+9)(x+y-9)则么算

(x-y+9)(x+y-9)则么算 (x-y)³+9(x-y)-6(x-y)² 计算:(x-y+9)(x+y-9) (x+y)²+6(x+y)+9 9(x-y)-12(y-x)^2 4+12(x-y)+9(x-y)^ (x+y)^2+6(x+y)+9 (x+y)^2-9(x+y)+18 9x+4y 计算 [ ( x+y ) ( x-y ) ] ^ 9 ÷ ( y-x )^ 8 ÷ ( -x-y )^9 计算.3(x-y)²/(y-x)³·(x-y)²÷9/y-x 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 4(x+y)²-12(x+y)(x-y)+9(x-y)² 81/8*(-x-y)^6*(x-y)^3*4/9(x+y)^4*(y-x)^2 计算:(x-y)(1/9x-y)-(1/3x-y)(1/3x+y) 因式分解因式分解9(x-y)²(x+y)+3(x+y)²(y-x) y+10x=x+y+9 10y+x=y+10x+27 3(x+y)的平方-7(x-y)-9(x+y)的平方-6(x-y)