问题
解答题
(1+
|
答案
(1+
)×(1-1 2
)×(1+1 2
)×(1-1 3
)×…×(1+1 3
)×(1-1 10
)1 10
=(1-
)×(1+1 2
)×(1-1 2
)×(1+1 3
)×…×(1-1 3
)×(1+1 10
),1 10
=
×(1 2
×3 2
×2 3
×4 3
×…×3 4
)×9 10
,11 10
=
×1×1 2
,11 10
=
.11 20