Math Flashcards
median
middle # of a series if odd, take average of two middle digits if even
mode
that appears the most
factors/GCF
71 = 2^3 x 3^3 - GCF between two #s is the repeated factors in each number
multiples/LCM
9, 18, 27, 36, etc. LCM = take factors of each number, multiple the greatest number of each factor
absolute value
can NEVER equal a negative number, |x-7| = both -5 and 5, if inequality, change sign AND -/+
Proportion
A C
- = -
B D
Special linear equations
X + 1 = consecutive integers
X + 2 = even/odd integers
Product property of exponents
X^m • x^n = x^m+n
Ex) (3m^5)(-4m^3) = -12m^8
Factoring polynomials
If c is negative, then signs will be different. If c is positive, then signs will be the same.
Factoring with prime numbers
Carry over, multiply, factor, divide, carry over
Arithmetic sequence formula
A(n) = a(1) + (n-1)d Where... A(n) is nth term A(1) is first term N is number of terms D is common difference
Arithmetic series formula
S(n) = n/2(a(1) + a(n)) Where... S(n) is sum of sequence N is number of terms A(1) is first term A(n) is nth term
Geometric sequence formula
A(n) = a(1) • r^(n-1)
Where…
R is common ratio
Geometric series formula
S(n) = [a(1)(1-r^n)]/1-r
Combinations
-order doesn't matter nCr = [n!]/[r!(n-r)!] Where... R is number you're selecting N is total number of choice Ex) 15 children in class, 5 needed for chores, possible combos -Calculator: 15, MATH, PRB, 3: nCr, 5
Permutations
-order does matter
nPr = [n!]/[(n-r)!]
-Ex) 10 horses running, possible combos for 1st, 2nd, and 3rd
Calculator: 2 instead of 3
Matrices
Multiply/divide/add/subtract with corresponding number
Quotient rule of exponents
X^m/x^n = x^(m-n)
Power rule of exponents
(x^m)^n = x^mn
Logarithmic functions
If b^x = y, then log(b)Y = x
Product property of logs
Log(b)MN = log(b) M + log(b) N
Quotient property of logs
Log(b) M/N = log(b) M - log(b) N
Power property of logs
Log(b) M^x = x • log(b) M
Change of base formula
Log(b) M = log(c) M / log(c) b
Discriminant
B^2 - 4ac
If 0, 1 real solution
If negative, non-real.
If positive, 2 real.
Parabola formula
Y=a(x-h)^2+k
Where…
(H,k) = vertex
A determines orientation and width
Circle equation
(X-h)^2 + (y-k)^2=r^2
(H,k) is center point
R is radius
Ellipse equation
[(x-h)^2]/a^2 + (y-k)^2/b^2 = 1
(H,k) center point equidistant from extremes on x and y
A is distance from center on x
B is distance from center on y
Hyperbola equation
Same for ellipse except minus sign
360 equals what in radians?
180?
90?
2pi
Pi
Pi/2
Complementary angles
Add up to 90