Sequences and Series

Question 0

Arithmetic sum

Answer 0

Sn = n ((a1 + an) / 2 )

Question 1

Arithmetic term

Answer 1

an = a1 + (n-1) d

Question 2

Geometric term

Answer 2

an = a1 * r^n-1

Question 3

Geometric sum

Answer 3

Sn = a1 * ((1-r^n) / (1-r))

Question 4

Infinite geometric sum

Answer 4

S = a1 / 1-r