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　　針對新GRE考試來說，特別是數學方法，大家在備考里需要掌握哪些重點內容才能讓備考效率更高呢?所以接下來要為大家分析一下關于新GRE數學備考的重點有哪些。

　　新GRE數學備考的重點一：Set

　　A set is a collection of objects or things. Each object in a set a member

　　or element of that set.Size of a set is the number of members in the set.

　　Example:

　　The set of even numbers between 2 and 10 is of size 5:{2,4,6,8,10}.

　　The set of primes between 2 and 10 is of size 4:{2,3,5,7}.

　　Remember:

　　Each member of set A belongs to A or is in the set A.

　　A set can not have repeating member:{1,3,1,2}is not a set.

　　Rearranging the order of the members does not change the set:{1,2,3}is same

　　as{3,2,1}.

　　GRE數學備考的重點二：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.

　　GRE數學備考的重點三：Permutation of Objects

　　The number of ways n distinct objects can be ordered is n!.

　　Example:

　　Number of ways 6 people can from a queue is 6!.

　　Number of ways 5 different cars can be parked in 5 parking spaces is

　　5!.

　　Remember:

　　This does not apply if there are identical objects or ordering does not

　　matter.

　　GRE數學備考的重點四：Permutation with Selection

　　The number of ways n objects drawn from a collection of m distinct objects

　　can be ordered is m!/(m-n)!.

　　Example:

　　Number of ways a queue of length 3 can be formed from a group of 5 people

　　is 5!/(5-3)!=5!/2!=5*4*3=60.

　　Number of possible top ten list for 150 movies is 150!/(150-10)!.

　　Remember:

　　This does not apply if there are identical objects or ordering does not

　　matter.

　　以上是環(huán)球教育小編跟大家分享的關于新GRE數學備考的重點有哪些，希望對大家有所幫助!在這里還要預祝大家在GRE考試中取得佳績!