18(x+y)^8(x-y)^7÷[3(x+y)^3(x-y)^3]^2

18(x+y)^8(x-y)^7÷[3(x+y)^3(x-y)^3]^2 [2(x-y)^5-8(x-y)^2(x+y)+6y(x-y)^2]÷2(x-y)^2[2(x-y)^3-8(x-y)^2(x+y)+6y(x-y)^2]÷2(x-y)^2 计算：(x-y)^7÷(y-x)^6+(-x-y)^3÷(x+y)^2 计算(x-y)^7÷(y-x)^6+9-x-y)^3÷(x+y)^2 解方程组24/(x+y) +24/(x-y) = 7/3 ,8/(x+y) +18/(x-y) = 4/3 4x-3y/x-2y÷6y-8x/y-2x (3x-4y)(5x-4y)-(7x-8y)(6y-5x) 3(x-y)^2-7(x-y)+8(y-x)^2+6(y-x)合并同类项. 计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x^2+xy+y^2) 3x÷(x-4y)+x+y÷(4y-x)-7y÷(x-4y)解方程 化简3x-2/(x+y)[(x+y)/3x-x-y]÷(x-y)/x 计算:1/(x-y)-1/(x+y)-2y/(x^2+y^2)-4y^3/(x^4+y^4)-8x^7/(x^8+y^8) 已知x^2+4y^2-4x+4y+5=0,求(2x^2+xy-y^2分之x^4-y^4)乘以（xy-y^2分之2x-y)÷（y分之x^2+y^2)^2的值已知xyz≠0,x+3y+7z=0,3x-4y-18z=0,求(x^2+2y^2+8z^2)分之（3x^2+5y^2+6z^2)的值 计算：(x-y)^8÷(y-x)^4×(x-y) 化简3(x-y)-7(x--y)+2(y-x) （-7x^2-8y^2）*(-x^2+3y^2) (3x-2y)(y-3x)-(2x-y)(3x+y) 已知实数x.y满足根号(x+y-8)+根号(8-x-y)=根号(3x-y-4)+根号(x-2y+7),求x,y x+y=1 5x-2y=8 3x-y=7 2x-y=3x表示y和用y表示x