第11页 - 数学 - 电子课本网

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$ \begin{aligned}解：原式&=\frac {b²}{a²}·a² \\ &=b² \\ \end{aligned}$

$ \begin{aligned}解：原式&=\frac {x²-1+1}{x²} \\ &=1 \\ \end{aligned}$

$ \begin{aligned}解：原式&=\frac {2+a-1}{(a+1)(a-1)} \\ &=\frac {a+1}{(a+1)(a-1)} \\ &=\frac {1}{a-1} \\ \end{aligned}$

$ \begin{aligned} 解：原式&=\frac {x+3}{x-1}·\frac {x-1}{x(x+3)} \\ &=\frac{1}{x} \\ \end{aligned}$

$解：原式=\frac {6-3(x-4)}{(x+4)(x-4)}·\frac {x-6}{x-6}$

$=\frac {18-3x}{(x+4)(x-4)}·\frac {x-4}{x-6}$

=$-\frac{3}{x + 4}$

$解：原式=\frac {2x²+3xy+y²}{x+y}-\frac {x²+2xy+xy+2y²}{x+y}$

$=\frac {x²-y²}{x+y}$

$=\frac {(x+y)(x-y)}{x+y}$

$=x-y$