计算.x²－y²分之x×－x²分之﹙x－y﹚².x＋1分之x－1×1－x分之1＋x.

计算.x²－y²分之x×－x²分之﹙x－y﹚².x＋1分之x－1×1－x分之1＋x.
计算.x²－y²分之x×－x²分之﹙x－y﹚².x＋1分之x－1×1－x分之1＋x.

计算.x²－y²分之x×－x²分之﹙x－y﹚².x＋1分之x－1×1－x分之1＋x.
x²－y²分之x×－x²分之﹙x－y﹚².
=x/(x+y)(x-y)×(x-y)²/(-x²)
=-(x-y)/x(x+y)

x＋1分之x－1×1－x分之1＋x.
=(x-1)/(x+1)×(x+1)/[-(x-1)]
=-1

x/(x²－y²)*﹙x－y﹚²/(－x²)-(x－1)/(x＋1)*1/(1－x)+x
=(x-1)/(x(x+1)+1/(x+1)+x
=(x-1+x+x3+x2)/(x(x+1)