Question

Quy đồng mẫu các phân thức sau:

a) \(\dfrac{3}{4x^3y^2}\)và\(\dfrac{2}{3x^3}\)

b) \(\dfrac{5}{x^2-6x+9}\)và\(\dfrac{3}{x^2-3x}\)

Answer 1

`a)MC: 12x^3y^2`

 `3/[4x^3y^2]=9/[12x^3y^2]`

 `2/[3x^3]=[8y^2]/[12x^3y^2]`

________________________________________

`b)MC:x(x-3)^2`

 `5/[x^2-6x+9]=5/[(x-3)^2]=[5x]/[x(x-3)^2]`

 `3/[x^2-3x]=3/[x(x-3)]=[3(x-3)]/[x(x-3)^2]=[3x-9]/[x(x-3)^2]`