The inverse of a 2 x 2 matrix - Inverse of Matrices
The inverse of a 2 x 2 matrix
In this lesson, we will learn how to find the inverse of a 2 x 2 matrix. You will learn that if two matrices are inverses of each other, then the product of the two matrices will result in an identity matrix. Next, you will learn how to find the inverse by using the formula below. You may find that the formula is hard to memorize. There is another way to find a 2 x 2 matrix without memorizing the formula, but it would require matrix row operations. You will see this method in the section "the inverse of 3 x 3 matrices with matrix row operations". Lastly, note that the inverse of a 2 x 2 identity matrix is just the identity matrix itself.
Lessons
Notes:
Let the matrices and be inverses. Then that means the following is true:
where is the identity matrix. To be more precise, we can say that since and are inverses, then is the same as , and so we can say that
Let be a matrix and you want to find the inverse (denote as ). Then we use the following formula:


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Intro Lesson
The Inverse of a 2 x 2 matrix overview:
