# Lesson Plan: Using Arithmetic Sequence Formulas Mathematics • Second Year of Secondary School

This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to write explicit and recursive formulas for arithmetic sequences to find the value of the 𝑛th term in an arithmetic sequence and how to find a term’s order given its value.

#### Objectives

Students will be able to

- calculate a specified term of an arithmetic sequence using the relation ,
- find the number of terms in a given arithmetic sequence,
- calculate the formula for the term of an arithmetic sequence,
- find the order of a specific term in an arithmetic sequence.

#### Prerequisites

Students should already be familiar with

- sequence notation,
- the definition of an arithmetic sequence,
- calculating the common difference of an arithmetic sequence.

#### Exclusions

Students will not cover

- listing an arithmetic sequence given information about it,
- arithmetic mean,
- arithmetic series,
- applications of arithmetic sequences,
- geometric sequence formulas or other types of sequences.