【小站教育】GMAT数学义.docVIP

GMAT数学讲义 GMAT数学备考关键词 一、知识点：准确掌握 二、词汇、表达法：读懂题目 三、熟练：平均两分钟一道题 考试相关问题 一、时间与题量 二、题型 三、机经与换题库 四、其它 If a and b are positive integers such that a – b and a/b are both even integers, which of the following must be an odd integer? （A） a/2 （B） b/2 （C）(a+b)/2 （D） (a+2)/2 （E） (b+2)/2 If M is the least common multiple of 90, 196, and 300, which of the following is NOT a factor of M? (A) 600 (B)700 (C) 900 (D) 2,100 (E) 4,900 复习注意事项 *战略上重视 *初等数学的思维 *解法力求稳妥清晰 *把握好DS题型 *熟练重于技巧 推荐复习步骤 *知识点查缺补漏 *背熟词汇 *复习课上所学 *OG，及其它相关资料 *机经： 第一章 算术 1. integer (whole number): 整数 * positive integer：正整数，从1开始，不包括0。 2. odd even number 奇数与偶数 * 凡整数均具有奇偶性，如－1是奇数，0是偶数。 * 奇+奇=偶，奇+偶=奇… 若干个整数相乘，除非都是奇数，其乘积才会是奇数… 例： If a and b are positive integers such that a – b and are both even integers, which of the following must be an odd integer? (A） (B） (C) (D) (E) 3. prime number composite number 质数与合数 * A prime number is a positive integer that has exactly two different positive divisors,1 and itself. * A composite number is a positive integer greater than 1 that has more than two divisors. * The numbers 1 is neither prime nor composite, 2 is the only even prime number. 4. factor(divisor) prime factor 因子和质因子 * 一个数能被哪些数整除，这些数就叫它的因子（因数、约数）。 * 因子里的质数叫质因子（数）。 例1： If n=4p, where p is a prime number greater than 2, how many different positive even divisors does n have, including n? (A) 2 (B) 3 (C) 4 (D) 6 (E) 8 例2： If the integer n has exactly three positive divisors, including 1 and n, how many positive divisors does n2 have? (A) 4 (B) 5 (C) 6 (D) 8 (E) 9 例3：1225有几个因子？ 例：What is the greatest prime factor of 2100 - 296? (A) 2 (B) 3 (C) 5 (D) 7 (E) 11 例：A positive integer n is said to be “prime-saturated” if the product of all the different positive prime factors of n is less than the square root of n. What is the greatest two-digit prime-saturated integer? (A) 99 (B) 98 (C) 97 (D) 96 (E) 95 5. the greatest common divisor (GCD) the