Sequences and Series

Question 1

What is an arithmetic sequence/progression?

Answer 1

A sequence where the difference between consecutive terms is constant

Question 2

What is the formula for the nth term of an arithmetic sequence?

Answer 2

u(n) = a + (n-1)d

Question 3

What is an arithmetic series?

Answer 3

A series where the sum of the terms of an arithmetic sequence.

Question 4

What is the formula for the sum of the first n terms of an arithmetic series?

Answer 4

S(n) = n/2 x (2a + (n-1)d)

or

S(n) = n/2 x (a + l) where l is the last term

Question 5

What is a geometric sequence/progression?

Answer 5

A sequence that has a common ratio between consecutive terms

Question 6

what is the formula for the nth term of a geometric sequence?

Answer 6

u(n) = ar^n-1

Question 7

What is a geometric series?

Answer 7

The sum of the terms of a geometric sequence

Question 8

What is the formula for the sum of the first n terms of a geometric series

Answer 8

S(n) = a(1-r^n)/1 - r r cannot equal 1