5/2x-4 +7/x+2 - 10/x²-4= 5/2(x-2) +7/(x+2) - 10/(x-2)(x+2)
= 5(x+2)/2(x+2)(x-2) + 7.2.(x-2)/2.(x+2)(x-2) - 10.2/2.(x+2)(x-2)
= (5x +10 +14x - 28 -20)/2.(x+2)(x-2)
= (19x -38)/2.(x+2)(x-2)
= 19(x-2)/2.(x+2)(x-2)
= 19/2.(x+2) = 19/(2x +4)
Chúc bạn học tốt^^