推 Ericdion :感謝!!! 05/05 21:54
※ 引述《Ericdion ( 由心出發 )》之銘言:
: 如題,題目照片中第9題,感謝
: https://www.dropbox.com/s/ehfv5oz313pahfr/2014-05-03%2009.46.06.jpg
: 類似題目還有103師大附中的題目
: https://www.dropbox.com/s/x4etorxxtuh46ro/2014-05-05%2019.00.33.jpg
原問題
(1 + w)^103
= ΣC(103,k) + wΣC(103,k) + w^2ΣC(103,k)
k=0,3,6... k=1,4,7... k=2,5,8...
= (1 + w)[ΣC(103,k)] - (w + 1)[ΣC(103,k)]
k=0,3,6... k=2,5,8...
(1 + 1)^103
= 2[ΣC(103,k)] + [ΣC(103,k)]
k=0,3,6... k=2,5,8...
所以
2^103 + (1+w)^102 2^103 + 1
ΣC(103,k) = ------------------- = -----------
k=0,3,6... 3 3
(a, b, c, d) = (3, 2, 103, 1)
: -----
: Sent from JPTT on my Asus PadFone T004.
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