High School Math Solutions - Matrix Inverse Calculator, Matrices (Part 2)

In the last two blog posts, I talked about how to find the inverse of a matrix and how to calculate the determinant of the matrix. Please review these two blog posts before continuing, if you are not familiar with either topic.

As you saw in the inverse blog post, calculating the inverse of a matrix can require a lot of steps and some time. In this blog post, I will go over a shortcut for calculating the inverse of a 2x2 matrix.

Here are the steps for calculating the inverse of a 2x2 matrix, using the shortcut:

1. Calculate the determinant of matrix A
                       Reminder:

2. Reorganize matrix A

3. Multiply matrix A by \frac{1}{det(A)}

These steps can be summarized by this formula:

Not too difficult, right? Let’s see some examples.

First example (click here):

1. Calculate the determinant of the matrix

2. Reorganize the matrix

3. Multiple the matrix by \frac{1}{det(A)}

Next example (click here):

1. Calculate the determinant of the matrix

2. Reorganize the matrix  

3. Multiple the matrix by \frac{1}{det(A)}

Last example (click here):

1. Calculate the determinant of the matrix

2. Reorganize the matrix  

3. Multiple the matrix by \frac{1}{det(A)}

This shortcut will help make calculating the inverse of a 2x2 matrix easier. That concludes our blog post series on matrices! For more help or practice on this topic, check out Symbolab’s Practice.

Until next time,

Leah