Question

2/x2-4 - 1/x2 -x =4+x/x(x+2)

Tick Đê

Answer 1

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

\(Đkxđ:x\ne0;x\ne\pm2\)

\(\dfrac{2}{\left(x-2\right)\left(x+2\right)}-\dfrac{1}{x\left(x-1\right)}-\dfrac{4+x}{x\left(x+2\right)}=0\)

\(\Leftrightarrow\dfrac{2x\left(x-1\right)}{x\left(x-2\right)\left(x+2\right)}-\dfrac{\left(x-2\right)\left(x+2\right)}{x\left(x-2\right)\left(x+2\right)}-\dfrac{\left(4+x\right)\left(x-2\right)}{x\left(x-2\right)\left(x+2\right)}=0\)\(\Rightarrow2x^2-2x-x^2+4-x^2+2x+8=0\)

\(\Leftrightarrow12=0\) (vô lí)

Vậy pt trên vô nghiệm