这次Q49+V34，680，比上次轻松的多，果然读的懂才是真本事。
好好复习+鸡精调味，下次就实现了。
做不出来答案的时候，很可能是题目读错了。
总结考点的目的在于构建自己的知识体系，而刷题的作用让你熟练运用+发现缺漏。
错误highlight：
当你在不等式里面去掉分母时，分母不为零一定加上！！！！
Terminology:
Arithmetic: integer
divisor(factor)
y is divisible by x or to be a multiple of x.
7 is a divisor or a factor of 28.
quotient and remainder
even integer, odd integer(including 0)
原书性质：
1. at least one factor of a product of integers is even, then the product is even;otherwise the product is odd;
2. If two integers are both even or both odd, then their sum and their difference are even, otherwise their sum and their difference are odd.
3. prime number, consecutive even integers, consecutive odd integers.
4. numerator, denominator
5. greatest common divisor (gcd), fractions are said to be
equivalent
.6. Least common multiple
7. Mixed Number: which is consist of a whole number and a fraction.
8. Decimals:Thousands,Hundreds, Tens, Ones or units.Tenths,Hundredths,Thousandths
9. Scientific notation, *10^5
10. Real Number–> on the number line
11. Distance–> absolute value
12. 5! 5 factorial
13. permutation and combination
14. Discrete Probability –> Continuous Probability
15. coefficient and constant terms, a second degree(or quadratic) polynomial in x.
16. Solving Two linear equations with two
unkonwns
17. Solving equations by factoring
18. Functions
Geometry:
1. Lines, intersecting lines and Angles
2. Perpendicular lines, Parallel Lines
3. Polygons (Convex):triangle,quadrilateral, pentagon and hexagon.
4. Triangles: equilateral triangle/ isosceles triangle; hypotenuse–>right angle;pythagorean theorem; the altitude of a triangle is the segment drawn from a vertex perpendicular to the side opposite that vertex. and base.
5. quadrilaterals: –> parallel –> parallelogram–>rhombus(邻边相同，对角线垂直平分，平分内角，面积等与对角线乘积一半)
parallelogram–>right angle –>rectangle–>equal length is a square.
Two sides that are parallel but not equal is a trapezoid.
Perimeter
6. Circles–》chord–>diameter, radius –> circumference–>Point of tangency–tangent
7. inscribed in the circle and circumscribed about the polygon.
8. rectangular solid –>face–>edge–>vertex–>volumn
9. Coordinate Geometry: Coordinate plane
10. x-y-intercept
数论（一）
考点1 四则 算对奇偶的影响
a +/- b = odd 一奇一偶
a +/- b = even 同奇偶
a*b*c*… = odd 全奇
a*b*c*… = even 有一偶
a/b = even a为偶数【这个很重要，如果结果为偶，则a定为偶数；但a/b都为偶，可能结果为奇数】n(n+1) = even
考点2 质因数/ 质数合数的性质
倍数 multiple
因数 factor/divisor
质数 prime number
合数 composite number
质因数 prime factor质数只有两个因数 1和本
合数 少有三个因数
2是质数中唯一的偶数考点2.2 质因数分解后的个数
Prime factor # 看有几个不同的数字
Factor # 各不同数字指数加一的乘积
1000的质因数和因数的个数分别是多少呢考点2.3
最大公约数 great common factor/divisor
最小公倍数 least common multipleGreatest common factor: product of common factor with lower power
Least common multiple: product of every factor with higher power数论（二）
考点1 连续正整数 Consecutive Positive Integers
n(n+1) 2整除
n(n+1)(n+2) 6整除
两个 续偶数相乘 8整除15*16*17*18 够 6整除 将18替代为18+6n 6整除
k(k+1)(k+2)(k+3)…某个数 a整除 则将任意一个其中的数字替换成+a, -a的数字 是 够 a整除。考点2 整除和余数 remainder
1. 余数的定义
2. 整除的公式
3. 指数的个位数周期
4. 数的整除特征含有变 的数除以一个常数
未知项 够整除 则余数固定
未知项不 整除 则余数不固定
代数（一）【看样子我对代数挺熟悉啊，怎么到线性代数就拉垮了呢？】
考点1：指数图像
这个图像就吊诡，a<0怎么说？没图像吗？
a < 0
，则正负取决于
x
的奇偶
考点2:这种多重嵌套真的不能用脑子，拿笔两三下解决了。结果我错选B
Of the following values of n, the value of (-1/5) ^ (-n) will be greatest for n=
(A) -3
(B) -2
(C) 0
(D) 2
(E) 3
考点
3
：根号计算
√n
的值大概是多少
Two positive numbers differ by 12 and their
reciprocals
differ by 4545. What is their product?
考点4:
If the equation x
2
-(m-2)x-(
n-4)
2
=0 has only one solution
, what is the product of m and n?
(A)4
(B)8
(C)10
(D)12
(E)16
我脑残还是反应慢？ b^2-4ac后呈现的结构是两个平方项之和=0，那只能是俩都为0.
shit！！！
考点 5 不等式
高次不等式 求解； 因式分解后奇穿偶不穿，符号看象限
分数不等式 正负判断
绝对值不等式 特征考察
If m > 0 and n > 0, is
𝑚
+
𝑥
𝑛
+
𝑥
(m+x)/(n+x)
>
𝑚
𝑛
m/n
(1) m < n
(2) x > 0
这题有趣！
考点
6:
绝对值的特征
|x – y|
表示的是数轴上两点的距离
例题
If both A and B are positive integers, is A = B?
(1) |A-n|=|B-n|
(2) n < 0
通过在数轴上画圈求解。
多个绝对值连用的不等式公式
x
和
y
同号：
|x
+
y|
=
|x|
+
|y|
x
和
y
异号：
|x
+
y|
<
|x|
+
|y|
x
和
y
同号：
|x
–
y|
=
| |x|
–
|y| |
x
和
y
异号：
|x
–
y|
>
| |x|
–
|y| |
x
和
y
同号，
|x| > |y|
: |
x
–
y|
=
|x|
–
|y|；否则xy异号
|x
–