Giúp tui với ạ ( tui cảm ơn nhá )

`a)` `4x-3(x-2)=7-x`

`<=>` `4x-3x+6=7-x`

`<=>` `4x-3x+x=7-6`

`<=>` `2x=1`

`<=>` `x=1/2`

Vậy `S={1/2}`

`b)` `x/{x-2}-{x-1}/{x+2}=3/{x^2-4}` `(`Đkxđ `x` $\neq$ `±2)`

`<=>` `{x^2+2x}/{x^2-4}-{x^2-x-2x-2}/{x^2-4}=3/{x^2-4}`

`<=>` `(x^2+2x)-(x^2-3x-2)=3`

`<=>` `5x+2=3`

`<=>` `5x=5`

`<=>` `x=1` `(`thỏa mãn`)`

Vậy `S={1}`