Lesson Plan: Three-by-Three Determinants Mathematics • First Year of Secondary School
This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to evaluate 3 × 3 determinants using the cofactor expansion (the Laplace expansion) or the rule of Sarrus.
Objectives
Students will be able to
- define minors and cofactors in a matrix,
- use the cofactors method (Laplace expansion) to evaluate a determinant,
- use the Sarrus method to evaluate a determinant.
Prerequisites
Students should already be familiar with
- determinants.
Exclusions
Students will not cover
- determinants of and higher-dimensional matrices,
- properties of determinants.
