推 cakeboy:這題是中山的嗎?(e^x-x-1/2x^2)(e^x)^3 02/10 21:42
→ ybite:不對，96中山資工問的問題完全不同（是問白旗0個或3個以上） 02/10 21:51
推 cakeboy:嗯嗯 那就不一樣了 02/10 21:54
→ ybite:式子應該沒錯，要求x^12/(12!)的係數，我算(4^12)/(4) 02/10 22:00
→ jimmy5566:謝了 02/10 22:02
A ship carries 48 flags,12 each of the colors red,white,blue,and black.
Twelve of these flags are placed on a vertical pole in order to communicate
a signal to other ships.How many of these signals use an even number of blue
flags and an odd number of black flags?
A(x)={(e^x+e^-x)/2}{(e^x-e^-x)/2}e^xe^x
式子這樣列對嗎?
最後化簡完答案會是多少,可以幫我算一下嗎
謝謝
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