计算1/6x-4y+2/4y^2-9x^2

计算：1/6x-4y+1/6x+4y-2y/4y^2-9x^2 [(x+2y)(x-2y)+4(x-y)^2-6x]/(6x)计算 计算.2x÷x/5x+3y^2-4y+4/2y-6·1/y+3÷12-6y/9-y^2 计算:(4xy(x-y)^-1+(x(y^-1)-(x^-1)y)/((x^-1)+(y^-1)))*(x+y)^-2 计算（4x^2y-9y)/(2x+3) 计算：4(x+2y)²-9(x-y)² 计算:2xy/(x+y)².(x+y)/4y 计算：[(x+2y)(x-2y)+4(x-y)^2]/6x 计算：（3x-4y）-[-（2y+x）+（x-3y）]-6x 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) 计算1/6x-4y+2/4y^2-9x^2 计算（2x-3y)(x+4y)-(3x+y)(x-2y)（2x-3y)(x+4y)-(3x+y)(x-2y) 3x+2=y 5X+4=Y 7X+6=Y 9X+8=y 11x=y要如何计算 计算(x-y)^7÷(y-x)^6+9-x-y)^3÷(x+y)^2 (x-3y)(y+2x)-(4y-3x)(3x+4y)计算 计算:(x-2y)(x+y)-2y(1-4y)= 计算:(x-y)^2*(x+y)^3*(-x-y)^3*(y-x)^4 计算：[（x+y）³-2(x+y)²-4(x+y)]÷（x+y)