Lesson: Finding the 𝑛th Term of a Geometric Sequence Mathematics • 9th Grade

In this lesson, we will learn how to write explicit and recursive formulas for geometric sequences to find the value of the 𝑛th term in a geometric sequence and how to find a term’s order given its value.

Lesson Plan

Students will be able to

find the recursive rule for a geometric sequence,
find the number of terms in a given geometric sequence,
find the term rule for a geometric sequence,
use the recursive rule or the term rule to find the value of a numbered term in a geometric sequence,
use the recursive rule or the term rule to find a term’s order in a geometric sequence when given its value.

Lesson Presentation

Lesson Video

Lesson Explainer

Lesson Worksheet

Q1:

Find the value of the second term of the geometric sequence , where .

Q2:

The recursive formula for a geometric sequence is and for . Give an explicit formula for the sequence.

Q3:

Find a formula for the general term of the geometric sequence .