Tính các biểu thức sau

a) Simplifying the expression:
5x - 4 / 2 + 4x + 4 / 9
= (5x - 4) / 2 + (4x + 4) / 9
= (9(5x - 4) + 2(4x + 4)) / (2 * 9)
= (45x - 36 + 8x + 8) / 18
= (53x - 28) / 18

b) Simplifying the expression:
x^2y - 6 / 2x^2y + 6 - xy^2 / 2x^2y
= (x^2y - 6) / (2x^2y + 6) - (xy^2) / (2x^2y)
= (x^2y - 6 - xy^2) / (2x^2y + 6)

c) Simplifying the expression:
4x - 1 / 3xy^2 - 7x - 1 / 3xy^2
= (4x - 1) / (3xy^2) - (7x - 1) / (3xy^2)
= (4x - 1 - 7x + 1) / (3xy^2)
= (-3x) / (3xy^2)
= -1 / y^2

d) Simplifying the expression:
x - 2y / x - y + y / x - y
= (x - 2y) / (x - y) + y / (x - y)
= (x - 2y + y) / (x - y)
= (x - y) / (x - y)
= 1

e) Simplifying the expression:
x^2 + y^2 / x^2 - y^2 - 2xy / x^2 - y^2
= (x^2 + y^2) / (x^2 - y^2) - (2xy) / (x^2 - y^2)
= (x^2 + y^2 - 2xy) / (x^2 - y^2)

g) Simplifying the expression:
3y - 2x / x - 2y - x - y / 2y - x
= (3y - 2x) / (x - 2y - x - y) / (2y - x)
= (3y - 2x) / (-3y - 3x) / (2y - x)
= (3y - 2x) / (-3(y + x)) / (2y - x)

h) Simplifying the expression:
2x^2 - x / x - 1 + x + 1 / 1 - x + 2 - 2x^2 / x - 1
= (2x^2 - x) / (x - 1 + x + 1) / (1 - x + 2 - 2x^2) / (x - 1)
= (2x^2 - x) / (2x) / (-2x^2 - x + 3) / (x - 1)