问题
解答题
(1)解分式方程:
(2)先化简,再求值:(
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答案
(1)方程变形得:
+1=-x-2 2x-1
,1.5 2x-1
去分母得:x-2+2x-1=-1.5,
解得:x=0.5,
经检验x=0.5是增根,原分式方程无解;
(2)原式=[
+1 x+1
]•(x-1)2 (x+1)(x-1)
=x+1 x-1
•x-1+(x-1)2 (x+1)(x-1)
=x+1 x-1
•x(x-1) (x+1)(x-1)
=x+1 x-1
,x x-1
当x=2时,原式=
=2.2 2-1