\(\dfrac{x+1}{x^2+x+1}-\dfrac{x-1}{x^2-x+1}=\dfrac{3}{x\left(x^4+x^2+1\right)}\)
\(\Leftrightarrow\dfrac{x\left(x+1\right)\left(x^2-x+1\right)-x\left(x-1\right)\left(x^2+x+1\right)}{x\left(x^2+x+1\right)\left(x^2-x+1\right)}=\dfrac{3}{x\left(x^2+x+1\right)\left(x^2-x+1\right)}\)
\(\Leftrightarrow x\left(x^3+1\right)-x\left(x^3-1\right)=3\)
=>2x=3
hay x=3/2