[理工] 離散生成函數
(1)
There are five kinds of balls: red, black, white, blue, and green.
We draw balls 8 times and then there are 5^8 combinations for these drawings.
(a) How many of these 5^8 drawings contain all the five colors of balls?
(b) How many drawing of (a) contain exactly three colors in the first 4 balls
of drawing the 8 times?
(2)
Consider the equation x+y+z=11, where x,y and z are nonegative integers.
How many solutions does it have if the condition 5>=x>=2, 6>=y>=3, 7>=z>=4
is satisfied?
求詳解
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※ 編輯: PTT007 來自: 220.136.83.236 (12/28 01:24)
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