问题 解答题
解答下列各题.
(1)化简:(
2x
x-3
-
x
x+3
)÷
x
x2-9

(2)解方程:
1
x
=
5
x+3

(3)请你先将
x2-2x
x-1
.(1-
1
x
)化简,再自选一个合理的x取值,求原式的值.
答案

(1)原式=

2x(x+3)-x(x-3)
(x+3)(x-3)
×
(x+3)(x-3)
x

=2(x+3)-(x-3)

=2x+6-x+3

=x+9;

(2)方程的两边同乘x(x+3),得

x+3=5x,

解得x=

3
4

检验:把x=

3
4
代入x(x+3)≠0.

∴原方程的解为:x=

3
4

(3)原式=

x(x-2)
x-1
×
x-1
x

=x-2,

∵x≠0,1,

∴取x=2,

∴原式=x-2=2-2=0.

补全对话,情景问答
单项选择题 A1型题