Question

B5: Thực hiện phép tính

d,1-2x/2x+2x/2x-1+1/2x-4x^2

e,x/xy-y^2+2x-y/xy-x^2

f, x^2/x^2-4x+6/6-3x+1/x+2

Answer 1

d: \(\dfrac{1-2x}{2x}+\dfrac{2x}{2x-1}+\dfrac{1}{2x-4x^2}\)

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

\(=\dfrac{-\left(4x^2-4x+1\right)+4x^2-1}{2x\left(2x-1\right)}\)

\(=\dfrac{-4x^2+4x-1+4x^2-1}{2x\left(2x-1\right)}=\dfrac{4x-2}{2x\left(2x-1\right)}=\dfrac{1}{x}\)

e: \(\dfrac{x}{xy-y^2}+\dfrac{2x-y}{xy-x^2}\)

\(=\dfrac{x}{y\left(x-y\right)}-\dfrac{2x-y}{x\left(x-y\right)}\)

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