Question

x+2/x-2-1/x=-2/x(x-2)

Answer 1

=>x(x+2)-x+2=-2

=>x^2+2x-x+2=-2

=>x^2+x+4=0

Δ=1^2-4*1*4=1-16=-15<0

=>Loại

Answer 2

`[x+2]/[x-2]-1/x=-2/[x(x-2)]`      `ĐK: x ne 0,x ne 2`

`=>x(x+2)-x+2=-2`

`<=>x^2+2x-x+2=-2`

`<=>x^2+x+4=0`

`<=>(x+1/2)^2+15/4=0`

`<=>(x+1/2)^2=-15/4` (Vô lí)

  `=>` Ptr vô nghiệm.