Sau khi thực hiện phép cộng các phân thức \(\dfrac{1}{\left(x-y\right)\left(y-z\right)}+\dfrac{1}{\left(y-z\right)\left(z-x\right)}+\dfrac{1}{\left(z-x\right)\left(x-y\right)}\), ta có kết quả là
0.\(\dfrac{1}{\left(x-y\right)\left(y-z\right)\left(z-x\right)}\).\(\dfrac{1}{\left(x-y\right)\left(y-z\right)}\).\(\dfrac{1}{\left(x-y\right)\left(z-x\right)}\).Hướng dẫn giải:\(\dfrac{1}{\left(x-y\right)\left(y-z\right)}+\dfrac{1}{\left(y-z\right)\left(z-x\right)}+\dfrac{1}{\left(z-x\right)\left(x-y\right)}\)
\(=\dfrac{z-x+x-y+y-z}{\left(x-y\right)\left(y-z\right)\left(z-x\right)}\)
\(=\dfrac{0}{\left(x-y\right)\left(y-z\right)\left(z-z\right)}=0\).
