Đáp án+Giải thích các bước giải:

 `5)\frac{3}{8x}-\frac{1}{2x}=\frac{1}{x^{2}}` `(đk:x\ne0)`

`\frac{3x}{8x^{2}}-\frac{4x}{8x^{2}}=\frac{8}{8x^{2}}`

`=>3x-4x=8`

`-x=8`

`x=-8(tmđk)`

Vậy `S={-8}`

`8)\frac{2}{3x}-\frac{1}{2x}=\frac{3}{4x^{2}}` `(đk:x\ne0)`

`\frac{2.4x}{12x^{2}}-\frac{1.6x}{12x^{2}}=\frac{3.3}{12x^{2}}`

`=>8x-6x=9`

`2x=9`

`x=9/2(tmđk)`

Vậy `S={9/2}`

`11)\frac{2}{x-1}=1` `(đk:x\ne1)`

`2=(x-1).1`

`(x-1).1=2`

`x-1=1/2`

`x=1/2+1`

`x=3/2(tmđk)`

Vậy `S={3/2}`

`14)\frac{2x-5}{x+5}=3(đk:x\ne-5)`

`2x-5=3.(x+5)`

`2x-5=3x+15`

`2x-3x=15+5`

`-x=20`

`x=-20(tmđk)`

Vậy `S={-20}`

`17)\frac{3x}{4x-3}=-2` `(đk:x\ne 3/4)`

`3x=-2.(4x-3)`

`3x=-8x+6`

`3x+8x=6`

`11x=6`

`x=6/11(tmđk)`

Vậy `S={-6/11}`

`20)3/2=6-\frac{x+10}{x-3}`

`(đk:x\ne3)`

`\frac{x+10}{x-3}=6-3/2`

`\frac{x+10}{x-3}=9/2`

`(x-3).9=2.(x+10)`

`9x-27=2x+20`

`9x-2x=20+27`

`7x=47`

`x=47/7(tmđk)`

Vậy `S={47/7}`

`23)\frac{5}{x-3}=\frac{x+2}{x-3}+3`

`(đk:x\ne3)`

`\frac{5}{x-3}=\frac{x+2}{x-3}+\frac{3.(x-3)}{x-3}`

`=>5=x+2+3x-9`

`5=4x-7`

`4x=12`

`x=3(ktmđk)`

Vậy phương trình vô nghiệm.

`26)\frac{(x+2)^{2}}{2x-3}-1=\frac{x^{2}+10}{2x-3}`

`(đk:x\ne3/2)`

`\frac{x^{2}+2.x.2+2^{2}}{2x-3}-\frac{2x-3}{2x-3}=\frac{x^{2}+10}{2x-3}`

`=>x^{2}+4x+4-(2x-3)=x^{2}+10`

`x^{2}+4x+4-2x+3-x^{2}-10=0`

`2x-3=0`

`2x=3`

`x=3/2(ktmđk)`

Vậy phương trình vô nghiệm.

`29)\frac{2}{x+1}+\frac{1}{3x+3}=1/6`

`(đk:x\ne-1)`

`\frac{2.6}{6.(x+1)}+\frac{2}{6.(x+1)}=\frac{x+1}{6.(x+1)}`

`=>12+2=x+1`

`14=x+1`

`x+1=14`

`x=13(tmđk)`

Vậy `S={13}`