1.
a^2 - 2ab + b^2: (a-b)(a-b)
2.
a^2 + 2ab + b^2: (a+b)^2
3.
adding exponents: x^a · x^b = x^(a+b)
4.
angles of triangle: add up to 180 degrees
5.
arc: Part of a circle connecting two points on the circle.
6.
area of sector: (n degree / 360 degrees) · pi · r^2
7.
area of triangle: area = (1/2)bh
8.
Arithmetic Sequences: t₁, t₁+ d, t₁+2d, ...
9.
average: average = sum of terms / number of terms
10.
average speed: average speed = total distance / total time
11.
Central Angle: An angle whose vertex is the center of the circle
12.
Chord: The distance from one point on the circle to another point on the circle.
13.
circle area: pi · r^2
14.
circle circumference: 2 · pi · r
15.
circle perimeter: 2 pi r
16.
complex numbers: i^0 = 1; i^1 = i; i^2 = -1; i^3 = -i; i^4 = 1; i^5 = i; i^6 = -1; i^7 = -i
17.
cos of an angle: adj / hyp
18.
degree to radian: degree# · (pi / 180 degrees)
19.
difference of squares: a^2 -b^2 = (a+b)(a-b)
20.
Direct Variation: y=kx
21.
distance formula: √[(x₂- x₁)^2 + (y₂- y₁)^2)]
22.
Dividing by a negative number in an inequality: You must flip the sign
23.
equation of circle: with midpoint (h,k) ... (x - h)^2 + (y - k)^2 = r^2
24.
equilateral: three equal sides, all angles = 60 degrees
25.
Factors: ex. factors of 52 are 2, 4, 13, and 26
26.
FOIL: (x+a)(x+b) = x^2 + (b+a)x + ab
27.
full circle: = 360 degrees
28.
fundamental counting principle: if an event can happen in N ways, and another, independent event can happen in M ways, then both events together can happen in N x M ways.
29.
Geometric Sequences: t₁, t₁· r, t₁· r², ...
30.
Graphing < or > on a coordinate plane: dotted line
31.
Graphing ≤ or < on a coordinate plane: shade downwards or to the left
32.
Graphing ≥ or > on a coordinate plane: shade upwards or to the right
33.
Graphing ≥ or ≤ on a coordinate plane: solid line
34.
Greatest Common Factor: ex. GCF of 200 and 60 is 20
35.
integers: ..., -3, -2, -1, 0, 1, 2, 3, ...
36.
intersecting lines: opposite angles are equal (each pair of angles along the same line add to 180 degrees)
37.
Inverse Variation: y=k/x
38.
isosceles: 2 equal sides, 2 equal angles
39.
Least Common Multiple: ex. LCM of 200 and 60 is 600
40.
length of arc: (n degree / 360 degrees) · 2 · pi · r
41.
length of triangle sides: length of 1 side is always less than the sum of the other 2
42.
logarithms: y = log(little b)x asks b^y = x
43.
median: median = middle value in the list
44.
mid-point formula: [(x₁+ x₂)/2 , (y₁+ y₂)/2]
45.
mode: mode = value in the list that appears most often
46.
Multiples: ex. multiples of 20 are 40, 60, 80, 100, ...
47.
multiplying exponents: (x^a)^b = x^(a·b)
48.
negative exponents: 1 / x^b = x^(-b)
49.
order of opperations: PEMDAS (Parentheses / Exponents / Multiply / Divide / Add / Subtract)
50.
parallelogram area: area = lh
51.
percentages: part = (percent / 100) x whole
52.
Point-Slope form: y - y₁= m(x - x₁)
53.
prime factors: 2, 3, 5, 7, 11, ...
54.
probability: probability = number of desired outcomes / number of total outcomes
55.
quadratic formula: [-b ± √(b² - 4ac)] / (2a)
56.
radian to degree: radian# · (180 degrees / pi)
57.
rationals: fractions (anything expessable as a ratio of integers)
58.
reals: integers, rationals, plus special #s (like √2 or pi)
59.
rectangle area: area = lw
60.
rectangular solid volume: volume = lwh
61.
right cylinder volume: volume = pi · r^2 · h
62.
roots: √(xy) = √x · √y
63.
Sector: The part of a circle that looks like a piece of pie. A sector is bounded by 2 radii and an arc of the circle.
64.
similar: same shape, corresponding angles are equal, corresponding sides are in proportion
65.
sin of an angle: opp / hyp
66.
slope formula: (y₂- y₁) / (x₂- x₁)
67.
Slope intercept form: y=mx+b
68.
special sin cos relationship: sin^2(angle) + cos^2(angle) = 1
69.
standard form: Ax + By=C, where A, B, and C are not decimals or fractions, where A and B are not both zero, and where A is not a negative
70.
subtracting exponents: x^a / x^b = x^(a-b)
71.
sum: sum = average x (number of terms)
72.
tan of an angle: opp / adj
73.
trapezoid area: area = [(base1 + base2) / 2] · h
74.
x^0: 1
