先化简,再选择一个合适的x值代入求值: ( x x+1 +1)÷(1- 3 x 2 1- x 2 )?

先化简,再选择一个合适的x值代入求值: ( x x+1 +1)÷(1- 3 x 2 1- x 2 )? 1 x-1 .
2025-05-17 15:59:54
推荐回答(1个)
回答1:

(
x
x+1
+1)÷(1-
3 x 2
1- x 2
)?
1
x-1

=
x+x+1
x+1
÷
1- x 2 -3 x 2
1- x 2
?
1
x-1

=
2x+1
x+1
÷
(1+2x)(1-2x)
(1+x)(1-x)
?
1
x-1

=
1-x
1-2x
?
1
x-1

=
1
2x-1

当x=0,则原式=-1.