原式=[3x/(x-2)-x/(x+2)]×[(x²-4)/x]
=[3x(x+2)/(x²-4)-x(x-2)/(x²-4)]×[(x²-4)/x]
=(3x²+6x-x²+2x)/x
=(2x²+8x)/x
=x(2x+8)/x
=2x+8