Formulas Flashcards
Formula: area of a triangle
A = 1/2 (base)(height)
What is the Pythagorean Theorem?
a2 + b2 = c2
How to calculate slope?
y2 – y1 / x2 – x1
Special Right Triangle
45-45-90
45-45-90
X : X : X √2
Special Right Triangle
30-60-90
30-60-90
X : X √3 : 2X
Sum of all internal angles in any polygon?
180 (n – 2)
n is the number of sides
One interior angle in a regular polygon
180 (n – 2) / n
n is the number of sides
Area of a circle
A = πr2
Circumference of a circle
C = 2 πr
Area of a trapezoid
A = (a + b)/2 * h
Even + Even
Even
Odd + Odd
Odd
Even + Odd
Odd
Even * Even
Even
Odd * Odd
Odd
Even * Odd
Even
Xm * Xn
Xm+n
Xm / Xn
Xm-n
(Xm)n
Xm*n
(X * Y)m
Xm * Ym
(X / Y)m
Xm / Ym
X0
1
X-n
1/Xn
√a * √b
√(a*b)
√a / √b
√(a/b)
What is the distance formula?
D = rate * time
√2
≈1.41
√3
≈ 1.7
√10
≈ 3.1
Simple interest formula
Value = principal (1 + rate*years)
Compound interest formula
Value = principal (1 + rate)time
Positive parabola
y = ax2 + bx + c
Negative parabola
y = -ax2 + bx + c
a is negative
Circle formula
(x–a)2 + (y–b)2 = r2
Center is (a,b), radius > 0
Absolute value formula
f(x) = |x|
Adding or subtracting numbers shifts the function up or down the x-axis
h(x) + c
Graph of h(x) is shifted upwards by c units
h(x) + c
Graph of h(x) is shifted upwards by c units
h(x) – c
Graph of h(x) is shifted downwards by c units
h(x + c)
Graph of h(x) is shifted left by c units
h(x – c)
Graph of h(x) is shifted right by c units
c*h(x) if c>1
Graph of h(c) is stretched vertically by factor of c
c*h(x) if 0<c<1
Graph of h(x) is shrunk vertically by factor of c
Real numbers (definition)
All rational and irrational numbers
Ex. 3, 0, 1.5, 3/2, √5
Everything except complex numbers
Xa = Xb
a = b
Negative number raised to even power
-52
Always positive
Negative number raised to odd power
-55
Always negative
How much of the data is within 2 standard deviations of the mean for a normal distribution?
95%
How much of the data is within 1 standard deviation of the mean for a normal distribution?
68%
Prime number (definition)
A number that is only divisible by 1 and itself
First 10 prime numbers
2, 3, 5, 7, 11, 13, 17, 19, 23, 29
Sum of arithmetic series
S = n/2 {2a + (n–1)d}
a = first term
d = common difference
n = number of terms
Parallel slopes are
Equal to each other
Perpendicular slopes are
Opposite reciprocals
5 -> -1/5
Volume of a cube
V = s3
Area of a cube
A = 6s2
Volume of a cylinder
V = πr2 h
Surface area of a cylinder
2 π r2 + 2 πrh
Finding the midpoint
((X1 ,X2)/2) , ((Y1 ,Y2)/2)
Mode
The number that appears most often in a set of values
