问题 解答题
(1)解方程:
1-x
2-x
-3=
1
x-2

(2)计算0.25×(-2)-2÷(16)-1-(π-3)0
(3)先化简(
x+1
x-1
+
1
x2-2x+1
x
x-1
,然后选取一个你喜欢的x的值代入计算.
答案

(1)方程两边同乘(x-2),

得:x-1-3(x-2)=1,

整理解得x=2.

经检验,x=2是原方程的增根,

故原方程无解.

(2)原式=0.25×

1
4
×16-1=1-1=0.

(3)(

x+1
x-1
+
1
x2-2x+1
x
x-1

=[

x+1
x-1
+
1
(x-1)2
]•
x-1
x

=

x+1
x
+
1
x(x-1)

=

x2-1
x(x-1)
+
1
x(x-1)

=

x
x-1

取x=2,得原式=2.

单项选择题 B型题
单项选择题