GRE数学重要知识点：组合

【导语】成功=时间+方法，自制力是这个等式的保障。世上无天才，高手都是来自刻苦的练习。而大家往往只看到“牛人”闪耀的成绩，忽视其成绩背后无比寂寞的勤奋。以下为“GRE数学重要知识点：组合”，欢迎阅读参考！更多相关讯息请关注®无忧考网！

　　Combinations

　　Number of ways we can select n objects from a group of m distinct objects is m!/(n!*(m-n)!).

　　Example:

　　Number of possible ways to pick 4 oscar nominations from a list of 50 movies is 50!/(4!*(50-4)!)=50!/(4!*46!)=50*49*48*47/24=230300.

　　Remember:

　　This does not apply if there are identical objects.