化简计算(x^-1/2y)(x^2+1/2y)(x^4+1/4y^2)

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 1、x(x-y)(x+y)-x(x+y)^2 计算:(x-2y)(1+x+2y+4y^2+2xy+x^2) 化简计算 [(x+1/4y)^2+(x-1/4y)^2](2x^2-1/8y^2) 计算(4x^2-2x^3+6x)/(-2x)-(x-1)^2y^2-4/y^2-y-6)+(y+2/y-3)/(y+1/ 分解因式计算:x^2(x-y)+(y-x)=?x^3+x^2+1\4x=?(2x+y)^2-(x-2y)^2=? 1) (2x+5y)(2x-5y)(-4x^2-25y^2) 2) [（x+y)(x-y)-(x-y)^2+2y(x-y (1)计算：a-(a^2)/(a+1)-1 (2)计算：3x/(x-4y)+(x+y)/(4y-x)-7y/(x-4y) (1)(2x-3y)的平方-(y+3x)(3x-y) (1~4是计算) (2)[(x-y)的平方+(x+y)的平方](x 计算：1/2x-1/x+y×（x+y/2x-x-y) 计算:1/(2x) - 1/(x+y)（(x+y)/(2x) - x - y） 化简求值：【(x+Y)(X-Y)-(X-Y)的平方+2Y（2-Y）】除4Y,其中X=1 Y=2