Sequences and Sums Flashcards
sequence
special type of function, domain is a consecutive set of integers
term
use subscripts to denote the input to the function so gvk instead of g(k)
index
variable k is the index in gvk
finite sequence
sequence with finite domain
initial index
first index in finite sequence (m)
final index
last index in finite sequence (n)
initial term
avm
final term
avn
infinite sequence
sequence with infinite domain, has an initial index of m
explicit formula
a sequence specifically showing how the value of term avk depends on k eg. dvk = 2k for k ≥ 1, starts with: 2,4,8,16..
increasing sequence
increasing if for every two consecutive indices, k and k+1, in the domain, avk < avk+1
non-decreasing sequence
if for every two consecutive indices, k and k+1, in the domain avk <= avk+1
decreasing sequence
if for every two consecutive indices in the domain avk > avk+1
non-increasing sequence
if for every two consecutive indices in the domain avk >= avk+1
geometric sequence
sequence of real numbers where each term after the initial term is found taking the previous term and multiplying by a fixed number (common ratio)