giup tuii voi a,hứa sẽ vote5* ạ,tui c ơn:33

`P = ((x^2 - 2)/(x^2+2x) + 1/(x+2)) . (x+1)/x`

`P = (x^2 - 2 + x)/(x^2+2x) . (x+1)/x`

`P = ((x-1)(x+2))/(x(x+2)) . (x+1)/x`

`P = (x^2-1)/(x^2)`

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`P = 5/2`

`(x^2-1)/(x^2) = 5/2`

`2x^2 - 2 = 5x^2`

`3x^2 = -2` (Vô lí vì `3x^2 >= 0 forall x`)

`->` Vô nghiệm

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`P = (x^2-1)/(x^2)`

`P = 1 - 1/(x^2)`

`-> P in Z -> 1/(x^2) in Z`

`x^2 in Ư(1) = {+-1}`

`-> x^2 = 1 (x^2 >=0 forall x)`

`-> x = +-1 (tmđk x ne 0 ; -2)`