Multiply: \acx2\ot\ac4x2\ac{x}{2} \ot \ac{4}{x^2}\acx2\ot\ac4x2.
\ac2x\ac{2}{x}\ac2x
\acx2\ac{x}{2}\acx2
\ac2x2\ac{2}{x^2}\ac2x2
2x2x2x