Geometric Sequences and Series Vocabulary

A ________ is the sum of the terms of a geometric sequence

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

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

• -177,147

• -19,683

• -59,049

• 118,098

The "a" value in f(x)=a(b)^x for geometric sequences represents what?

• first term

• term we're looking for, minus one

• common difference

• common ratio

• initial value

• increment

• starting point

• change rate

• common ratio

• opens up/down

• distance

• slope

• first term

• common difference

• common difference

• wanted term

• common ratio

• first term

• common difference

• wanted term

• common ratio

• first term

An infinite series exists for which of the following situations?

• An arithmetic series

• A geometric series

• A geometric series with | r | > 1

• A geometric series with | r | < 1

Find the common ratio: 16, 8, 4, 2, ...

• r = 2

• r = 8

• r = 1/4

• r = 1/2