Sequences, Series, and Probability Flashcards
nPr
Permutation, order matters,
n!/(n-r)!
nCr
Combination, order doesn’t matter, nPr/r! or n!/(n-r)!r!
Binomial Theorem
nC0 a^n + nC1 a^n-1 b1 + … + nCn-1 a^1 b^n-1 + nCn b^n
Sequence
List of #s with a certain pattern, finite or infinite, can converge or diverge
Series
Sum of the terms of a sequence, finite or infinite
Arithmetic Sequence
A sequence with a common difference between terms
Arithmetic RF
an = an-1 + d
Arithmetic EF
an = a1 + d(n-1)
Arithmetic Series Formula
Sn = n/2(a1 + an)
Geometric Sequence
A sequence with a common ratio between terms
Geometric EF
an = a1 • (r)^(n-1)
Geometric RF
an = r(an-1)
Sigma (Summation) Notation
n of last term —————— \ \ \ Formula in / terms of n / / —————— n of first value
Partial Sum of Geometric Series
Sn = a1(1-r^n)/1-r
Converging Geometric Series
When does it converge?
A series will only converge if |r| < 1
S = a1/1-r