Geometric Sequences

Find the common ratio for the geometric sequence.

• 10

• 1/2

• 2

• 4

Is the sequence -432, 72, -12, 2,...geometric?

• yes

• no

Write the explicit formula for the geometric sequence.

• a_n = 4(3)^n-1

• a_n = 3(4)^n-1

• a_n = -4(3)^n-1

• a_n = 3(-4)^n-1

What is the 14th term of the geometric sequence?

• 14,348,907

• 4,782,969

• 1,594,323

• 45

Given the sequence: 125, 25, 5, .... Write the rule a_n using the geometric sequence formula:

• a_n = (125)(1/5)^(n-1)

• a_n = 625(1/5)^(n-1)

• a_n = 625(5)^(n-1)

• a_n = 125 + 5n

A geometric sequence has a common ration(r) of 3 and the 8th term (a₈) is 13,122. What is the first term of the sequence (a₁)?

• 3

• 6

• 18

• 2

What is the 9^th term in a geometric sequence with a common ratio of 2 and a first term of 3?

• 384

• 768

• 1,536

• 27

Find the first four terms of the sequence given the rule:
a_n = 4(5)^n-1

• 20, 100, 500, 2500

• 5, 20, 80, 320

• 4, 20, 100, 500

• 4, 9, 14, 19

Find a₁₂ in the sequence -1, -3, -9, -27, ...

• -177,147

• -19,683

• -59,049

• 118,098

Find the next three terms: 4, 12, 36, 108, ...

• 324, 972, 2916

• 972, 2916, 8748

• 405, 1215, 3645