Thực hiện phép tính: a) 5/2x^2y + 3/5xy^2 + x/y^3; b) x + 1/2x + 6 + 2x + 3/x(x + 3)

lam tinh cong cac phan thuc sau:
a)5/2x^2 y+3/5xy^2+x/y^3;
b)x+1/2x+6 +2x+3/x(x+3);
c)3x+5/x^2-5x +25-x/25-5x;
d)x^2+ x^4+1/1-x^2 +1;
e)4x^2-3x+17/x^3-1 + 2x-1/x^2+x+1 +6/1-x.
tim phan thuc doi cua 1-x/x.
minh dang can gap phien cac ban giai bai nay ra tung buoc ho minh