问题
解答题
先化简,再求值:
|
答案
÷(x-x-1 x
)=1 x
÷x-1 x
=x2-1 x
•x-1 x
=x (x+1)(x-1) 1 x+1
当x=
-1时,原式=3
=1 3
.3 3
先化简,再求值:
|
÷(x-x-1 x
)=1 x
÷x-1 x
=x2-1 x
•x-1 x
=x (x+1)(x-1) 1 x+1
当x=
-1时,原式=3
=1 3
.3 3