问题
解答题
先化简代数式:(
|
答案
(
+x-1 x+1
)÷2x x2-1 1 x2-1
=(
+(x-1)2 (x+1)(x-1)
)÷2x x2-1
(2分)1 x2-1
=
×(x2-1)(4分)x2+1 x2-1
=x2+1;(15分)
当x=0时,原式的值为1.(6分)
说明:只要x≠±1,且代入求值正确,均可记满分(6分).
先化简代数式:(
|
(
+x-1 x+1
)÷2x x2-1 1 x2-1
=(
+(x-1)2 (x+1)(x-1)
)÷2x x2-1
(2分)1 x2-1
=
×(x2-1)(4分)x2+1 x2-1
=x2+1;(15分)
当x=0时,原式的值为1.(6分)
说明:只要x≠±1,且代入求值正确,均可记满分(6分).