Question

Cộng các phân thức cùng mẫu thức :

a) \(\dfrac{1-2x}{6x^3y}+\dfrac{3+2y}{6x^3y}+\dfrac{2y-4}{6x^3y}\)

b) \(\dfrac{x^2-2}{x\left(x-1\right)^2}+\dfrac{2-x}{x\left(x-1\right)^2}\)

c) \(\dfrac{3x+1}{x^2-3x+1}+\dfrac{x^6-6x}{x^2-3x+1}\)

d) \(\dfrac{x^2+38x+4}{2x^2+17x+1}+\dfrac{3x^2-4x-2}{2x^2+17x+1}\)

Answer 1

a: \(=\dfrac{1-2x+3+2y+2y-4}{6x^3y}=\dfrac{-2x+4y}{6x^3y}=\dfrac{-2\left(x-2y\right)}{6x^3y}=\dfrac{-x+2y}{3x^3y}\)

b: \(=\dfrac{x^2-2+2-x}{x\left(x-1\right)^2}=\dfrac{x\left(x-1\right)}{x\left(x-1\right)^2}=\dfrac{1}{x-1}\)

c: \(=\dfrac{3x+1+x^6-3x}{x^2-3x+1}\)

\(=\dfrac{x^6+1}{x^2-3x+1}\)

d: \(=\dfrac{x^2+38x+4+3x^2-4x-2}{2x^2+17x+1}\)

\(=\dfrac{4x^2+34x+2}{2x^2+17x+1}=2\)