Giúp e vs!

Cảm ơnn!.

`a, 5/(3x - 2) - 1/(2 - 3x)`   (ĐKXĐ: `x \ne 2/3`)

`= 5/(3x - 2) + 1/(3x - 2)`

`= (5 + 1)/(3x - 2)`

`= 6/(3x - 2)`

`b, 1/(2(x + 1)) + 2/(x - 1) - 4/(x^2 - 1)`  (ĐKXĐ: `x \ne +-1`)

`= (x - 1)/(2(x - 1)(x + 1)) + (2.2(x + 1))/(2(x - 1)(x + 1)) - (4.2)/(2(x - 1)(x + 1))`

`= ((x - 1) + 4(x + 1) - 8)/(2(x - 1)(x + 1))`

`= (x - 1 + 4x + 4 - 8)/(2(x - 1)(x + 1))`

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

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

`= 5/(2(x + 1))`

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