Question

Answer 1

Bài 3: 

a: \(=\dfrac{4x-1-7x+1}{3x^2y}=\dfrac{-3x}{3x^2y}=\dfrac{-1}{xy}\)

b: \(=\dfrac{3x+5-7+2x}{2\left(5x-2\right)}=\dfrac{5x-2}{2\left(5x-2\right)}=\dfrac{1}{2}\)

c: \(=\dfrac{3x}{5\left(x+y\right)}-\dfrac{x}{10\left(x-y\right)}\)

\(=\dfrac{6x}{10\left(x+y\right)}-\dfrac{x}{10\left(x-y\right)}\)

\(=\dfrac{6x^2-6xy-x^2-xy}{10\left(x+y\right)\left(x-y\right)}=\dfrac{x^2-7xy}{10\left(x+y\right)\left(x-y\right)}\)