Geometric sequences 3

Determine whether the sequence is arithmetic, geometric, or neither.

• arithmetic
• geometric
• neither

Determine whether the sequence is arithmetic, geometric, or neither.

• arithmetic
• geometric
• neither

Write the explicit formula for the geometric sequence.

• a_n = 7(1)ⁿ
• a_n = 7(-1)ⁿ
• a_n = 7(-1)^n-1
• a_n = -1(7)^n-1

Find the common ratio for the geometric sequence.

• 2/3
• 3/2
• -2/3
• -3/2

Find the common ratio for the geometric sequence.

• 10
• 1/2
• 2
• 4

Find the common ratio: 64, -16, 4, -1, ...

• r = -8
• r = -1/4
• r = -4
• r = 4

Determine whether the sequence is arithmetic, geometric, or neither.

• arithmetic
• geometric
• neither

Find the common ratio for the geometric sequence.

• -4
• 4
• 1/4
• -1/4

Write the explicit formula for the following geometric sequence:

100, 50, 25, 12.5, ...

• a_n = 2(100)^n-1

• a_n = 100(2)^n-1

• a_n = 100(1/2)^n-1

• a_n = (1/2)(100)^n-1

Find a₁₂ in the following geometric sequence:

-1, -3, -9, -27, ...

• -177,147

• -19,683

• -59,049

• 118,098