y=(2x+2)/(x^2+2x-3),求它的n阶导数

x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 3^x+2x=y,x x(x-y)2-(y-x)3 [2/3x-2/x+y(x+y/3x-x-y)]/x-y/x 化简：{2/3x-2/(x+y)[(x+y)/3x-x-y]}/(x+y)/x 计算2/3x-2/x+y(x+y/3x-x-y)/x-y/x 化简3x-2/(x+y)[(x+y)/3x-x-y]÷(x-y)/x (x-y) (x-2y)+(x+2y) (x-3y)-2(x-3y) (x-4y)= (x+y)(x-y)+(x-y)平方-(x-y)(3x-y) 其中x=-2 y=3分之一 已知x-y/x+y=3,求代数式5(x-y)/x+y-x+y/2(x-y) (x+y)(2x-3y)=? 函数,y=3x/(x^2+x+1) ,x 函数y=3x/(x^2+x+1) （x (x^3-2x^2+xy^2)/(x-y)+(x+y)(y-x)=? 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 若2x=3y,则(x*x+y*y)/x*x=? 因式分解x(x+y)(x-y)-x(x+y)^2 化简 3x(x^2-x-1)-(x+1)(3x^-x) X^3(x-y)+x(y-x)