GRE数学指南阅读笔记

前言

总结自Official GRE数学官方指南，虽然听说数学很简单，但是还是要了解一下具体怎么考。

（需要认识如下英文）

学科	具体考点
Arithmetic	properties and types of integers: divisibility, factorization, prime numbers, remainders, odd and even integers, arithmetic operations, exponents, roots
	concept: estimation, percent, ratio, rate, absolute value, the number line, decimal representation, sequences of numbers
Algebra	operations with exponents, factoring and simplifying algebraic expressions, relations, functions,
	equation and inequalities, linear and quadratic equations and inequalities, simultaneous equations and inequalities, setting up equations to solve word problems, coordinate geometry, graphs of functions, equations, and inequalities, intercepts, and slopes of lines
Geometry	parallel lines, perpendicular lines, circles, triangles, isosceles equilaterals, and 30°-60°-90° triangles, quadrilaterals, polygons, congruent and similar figures, three-dimensional figures, area, perimeter, volume, the Pythagorean theorem, angle measurement in degree (no proof involved)
Data analysis	descriptive statistics: mean, median, mode, range, standard deviation, interquartile range, quartiles and percentiles
	data extraction: line graphs, bar graphs, circle graphs, boxplots, scatterplots and frequency distributions
	elementary probability: independent events and compound events, random variables, probability distributions, normal distributions, combinations, permutations, Venn diagrams (no inferential statistics involved)

四分位数概念类似于中位数，但其将整个数据集分为四份；可通过如下方式计算

即上四分位数Q3和下四分位数Q1的差。

百分位数也和四分位数类似（边界也有争议），其表示的概念可举例为：“95百分位（的数）——数据中95%的数小于该数“。

在无法凑整分割时具体计算也有最近序数（看更靠近哪个）、插值等多种解决手段。

故四分位数又可称为第25（75）个百分位数，中位数称为第50个百分位数。

显示出一组数据的最大值和最小值（延长线端点）、中位数（箱中线）、及上下四分位数（箱边界），有时也会用点表示平均值。

题型	简要描述
Quantitative Comparison questions	给两个量，比大小。在”A大于B“，”A小于B“，”A等于B“，”不一定“四个选项里选一个。
Multiple-choice questions - Select One Answer Choice	多项选择单选题，支持排除法
Multiple-choice questions - Select One or More Answer Choices	多项选择多选题（~~一般不会选很多？~~）
Numeric Entry questions	填空题，注意数字单位以及小数点要求（允许使用计算器）