Đáp án:
`\text{Em tham khảo}`
Giải thích các bước giải:
`a,A=(3x-2)/x-(x-7)/(x-5)-10/(x^2-5x)`
`=((3x-2)(x-5))/(x^2-5x)-(x(x-7))/(x^2-5x)-10/(x^2-5x)`
`=((3x-2)(x-5)-x(x-7)-10)/(x^2-5x)`
`=(3x^2-17x+10-x^2+7x-10)/(x^2-5x)`
`=(2x^2-10x)/(x^2-5x)`
`=(2x(x-5))/(x(x-5))`
`=2`
`b,B=A.(x+1)/(x-1)`
`=(2x+2)/(x-1) in Z`
`=>2x+2 vdots x-1`
`=>2x-2+4 vdots x-1`
`=>4 vdots x-1`
`=>x-1 in Ư(4)={+-1,+-2,+-4}`
`=>x in {0,2,-1,3,-3,5}`
