risultato
320)
$\dfrac{x^2-2x+1}{x^2-4}·\dfrac{x^2+3x+2}{x^2-3x}·\dfrac{x^3-2x^2}{x^2-1}=$
$=\dfrac{(x-1)^2}{(x-2)(x+2)}·\dfrac{(x+2)(x+1)}{x(x-3)}·\dfrac{x^2(x-2)}{(x-1)(x+1)}=$
$= \dfrac{(x-1)^\cancel{2}}{\cancel{(x-2)}\cancel{(x+2)}}·\dfrac{\cancel{(x+2)}\cancel{(x+1)}}{\cancel{x}(x-3)}·\dfrac{x^\cancel2\cancel{(x-2)}}{\cancel{(x-1)}\cancel{(x+1)}}=$
$=\dfrac{x-1}{1}·\dfrac{1}{x-3}·\dfrac{x}{1}=$
$= \dfrac{x(x-1)}{x-3}$