Đáp án:
`= 1/{x - 2}`
Giải thích các bước giải:
`c`
`x/{x - 2} + {2 - x}/{x + 2} + {6 - 5x}/{x^2 - 4}` (ĐKXĐ: `x ne +- 2`)
`= x/{x - 2} + {2 - x}/{x + 2} + {6 - 5x}/{(x - 2)(x + 2)}`
`= {x(x + 2)}/{(x - 2)(x + 2)} + {(2 - x)(x - 2)}/{(x - 2)(x + 2)} + {6 - 5x}/{(x - 2)(x + 2)}`
`= {x^2 + 2x}/{(x - 2)(x + 2)} - {(x - 2)(x - 2)}/{(x - 2)(x + 2)} + {6 - 5x}/{(x - 2)(x + 2)}`
`= {x^2 + 2x}/{(x - 2)(x + 2)} - {x^2 - 4x + 4}/{(x - 2)(x + 2)} + {6 - 5x}/{(x - 2)(x + 2)}`
`= {x^2 + 2x - (x^2 - 4x + 4) + 6 - 5x}/{(x - 2)(x + 2)}`
`= {x^2 + 2x - x^2 + 4x - 4 + 6 - 5x}/{(x - 2)(x + 2)}`
`= {(x^2 - x^2) + (2x + 4x - 5x) + (6 - 4)}/{(x - 2)(x + 2)}`
`= {x + 2}/{(x - 2)(x + 2)}`
`= 1/{x - 2}`
`#SunHee`
