新GRE數(shù)學考試復習重要考點之排列

俗話說：“工欲善其事必先利其器”。很多參加了新版gre考試的同學都覺得數(shù)學有點難度，相信這其中的原因還是由于考生在新版gre數(shù)學復習時沒有把基礎(chǔ)打牢。如果新版gre數(shù)學基本考點都沒有復習到，如何能拿到分數(shù)呢?所以說，想要新版gre數(shù)學考好，復習的時候一定要把基本概念和重要考點都弄扎實。
    今天針對新版gre數(shù)學復習，小編給大家整理的是關(guān)于Combinations of Choices的相關(guān)內(nèi)容，這些概念在考試中一定會考到的。希望考生能再接再厲，取得一個好成績，突破新版gre數(shù)學難的困境。
    　　新版gre數(shù)學復習重要考點：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.
    　　新版gre數(shù)學復習重要考點：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.
    很多新版gre數(shù)學復習考點都是高中時候?qū)W到的知識點，考生不要過于緊張，把基本概念弄明白，再記住一些新版gre數(shù)學必備的詞匯，那么相信新版gre數(shù)學應該沒有問題。