问题
解答题
已知
|
答案
(
-1 1-x
)÷(1 1+x
+x)x x2-1
=-
÷2x (1-x)(1+x) x3 (1-x)(1+x)
=-
•2x (1-x)(1+x)
=-(1-x)(1+x) x3 2 x2
∵
=x2 x2-2
,1 1-
-2 3
∴
=1-x2-2 x2
-2
,3
即-
=-(2 x2
+2
)3
∴原式=-(
+2
).3
已知
|
(
-1 1-x
)÷(1 1+x
+x)x x2-1
=-
÷2x (1-x)(1+x) x3 (1-x)(1+x)
=-
•2x (1-x)(1+x)
=-(1-x)(1+x) x3 2 x2
∵
=x2 x2-2
,1 1-
-2 3
∴
=1-x2-2 x2
-2
,3
即-
=-(2 x2
+2
)3
∴原式=-(
+2
).3