Chapter 8 formulas algebra 2 Flashcards
1
Q
arithmetic explicit
A
a(n): a(1)+(n-1)d
where d=common difference
2
Q
arithmetic recursive formula (total based on the last 2 terms)
A
a(n)=a(n-1)+d, a=?
starting place needed
3
Q
sum of arithmetic sequences
A
s(n)=(n/2)(a1+an) OR (n/2)(2a1+(n-1)d)
4
Q
geometric explicit
A
a(n)=a1 (r)^n-1
5
Q
geometric recursive
A
a(n)=a(n-1)(r), a1=?
6
Q
total of geometric sequences
A
sn=a1((1-r^n)/1-r)
7
Q
sum of infinite geometric sequence
A
s=a1/(1-r)
8
Q
fibbonacis sequence
A
an=a(n-1)+a(n-2), a1=? and a2=?
