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计算:(1)x2+1x2−1−x−2x−1÷x−2x;(2)(3xy-2)2÷(-2x-1y).

题目详情
计算:
(1)
x2+1
x2−1
x−2
x−1
÷
x−2
x

(2)(3xy-22÷(-2x-1y).
▼优质解答
答案和解析
(1)
x2+1
x2−1
x−2
x−1
÷
x−2
x
=
x2+1
(x+1)(x−1)
 − 
x−2
x−1
 • 
x
x−2
=-
1
x+1

(2)(3xy-22÷(-2x-1y)=
9 x2y−4
−2  x−1y  
=-
9 x3
2 y5