计算: (1)x/x−1-x+3/x2−1•x2+2x+1x+3;(2)(1/x−2-1)÷3−xx2−4.
问题描述:
计算:
(1)
-x x−1
•x+3
x2−1
;(2)(
x2+2x+1 x+3
-1)÷1 x−2
. 3−x
x2−4
答
(1)原式=
−x x−1
•x+3 (x+1)(x−1)
(x+1)2
x+3
=
−x x−1
x+1 x−1
=-
;1 x−1
(2)原式=
÷3−x x−2
3−x (x+2)(x−2)
=
•3−x x−2
(x+2)(x−2) 3−x
=x+2.