Question

Qui đồng mẫu thức các phân thức:

\(\dfrac{2}{x^3-y^3};\dfrac{1}{x+y}\) và \(\dfrac{2x+1}{x^2-y^2}\)

Answer 1

\(\dfrac{2}{x^3-y^3}=\dfrac{2}{\left(x-y\right)\left(x^2+xy+y^2\right)};\dfrac{1}{x^2-y^2}=\dfrac{1}{\left(x-y\right)\left(x+y\right)}\)MTC: (x-y)((x+y)(x²+xy+y²)

\(\dfrac{2}{x^3-y^3}=\dfrac{2}{\left(x-y\right)\left(x^2+xy+y^2\right)}=\dfrac{2\left(x+y\right)}{\left(x+y\right)\left(x-y\right)\left(x^2+xy+y^2\right)}\)\(\dfrac{1}{x+y}=\dfrac{\left(x-y\right)\left(x^2+xy+y^2\right)}{\left(x-y\right)\left(x+y\right)\left(x^2+xy+y^2\right)}\)

\(\dfrac{2x+1}{x^2-y^2}=\dfrac{2x+1}{\left(x-y\right)\left(x+y\right)}=\dfrac{\left(2x+1\right)\left(x^2+xy+y^2\right)}{\left(x-y\right)\left(x+y\right)\left(x^2+xy+y^2\right)}\)