计算(1)x+1分之x - x-1分之1 - x²-1分之2 (2)(x分之1+y分之1)² - (x分之1-y分之1)²(3)(x²-x-6分之x²-4 - x-3分之x+2)除以 x-3分之4

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计算(1)x+1分之x - x-1分之1 - x²-1分之2 (2)(x分之1+y分之1)² - (x分之1-y分之1)²(3)(x²-x-6分之x²-4 - x-3分之x+2)除以 x-3分之4

计算(1)x+1分之x - x-1分之1 - x²-1分之2 (2)(x分之1+y分之1)² - (x分之1-y分之1)²(3)(x²-x-6分之x²-4 - x-3分之x+2)除以 x-3分之4
计算(1)x+1分之x - x-1分之1 - x²-1分之2 (2)(x分之1+y分之1)² - (x分之1-y分之1)²
(3)(x²-x-6分之x²-4 - x-3分之x+2)除以 x-3分之4

计算(1)x+1分之x - x-1分之1 - x²-1分之2 (2)(x分之1+y分之1)² - (x分之1-y分之1)²(3)(x²-x-6分之x²-4 - x-3分之x+2)除以 x-3分之4
(1)x+1分之x - x-1分之1 - x²-1分之2
=[x(x-1)-(x+1)-2]/(x²-1)
=(x²-x-x-1-2)/(x+1)(x-1)
=(x-3)(x+1)/(x+1)(x-1)
=(x-3)/(x-1)
(2)(x分之1+y分之1)² - (x分之1-y分之1)²
=(1/x+1/y+1/x-1/y)(1/x+1/y-1/x+1/y)
=2/x×2/y
=4/xy
(3)(x²-x-6分之x²-4 - x-3分之x+2)除以 x-3分之4
=[(x+2)(x-2)/(x-3)(x+2)-(x+2)/(x-3)] ×(x-3)/4
=[(x-2)/(x-3)-(x+2)/(x-3)]×(x-3)/4
=-4/(x-3)×(x-3)/4
=-1