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Inverse Matrix Calculator

Calculate matrix inverse step-by-step with our advanced linear algebra calculator. Perfect for finding A1A^{-1} for 2×22 \times 2, 3×33 \times 3, and larger matrices with detailed explanations.

Inverse Matrix Calculator

Enter a matrix and calculate its inverse with step-by-step solutions

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Master Matrix Inverses with Our Advanced Calculator

Our inverse matrix calculator is designed to help students, teachers, and professionals calculate matrix inverses efficiently. Whether you're working on linear algebra homework, preparing foruniversity mathematics exams, or tackling engineering problems, this tool provides comprehensive step-by-step solutions that enhance your understanding of matrix algebra.

The inverse matrix calculator computes the inverse of square matrices using various methods including Gauss-Jordan elimination, adjugate method, and special formulas for 2×22 \times 2 and 3×33 \times 3 matrices. Our linear algebra calculator is particularly useful for university linear algebra courses and engineering applications, where matrix inverses are used to solve systems of equations, perform coordinate transformations, and model complex systems.

Perfect for high school linear algebra students learning matrix inverses, university studentsin advanced mathematics courses, engineering students applying matrix inverses to real-world problems, andprofessionals who need quick mathematical solutions. The inverse matrix calculator provides not just answers, but detailed explanations that help you understand the underlying concepts and improve your mathematical skills.

Methods for Calculating Matrix Inverses

Matrix SizeFormulaMethodDifficulty Level
2×2 Matrix

A1=1det(A)(dbca)A^{-1} = \frac{1}{\det(A)} \begin{pmatrix} d & -b \\ -c & a \end{pmatrix}

Adjugate methodIntermediate
3×3 Matrix

Gauss-Jordan elimination or adjugate

Row operations or cofactor expansionAdvanced
n×n Matrix

A1=1det(A)adj(A)A^{-1} = \frac{1}{\det(A)} \text{adj}(A)

Gauss-Jordan eliminationAdvanced
Diagonal Matrix

Aii1=1aiiA^{-1}_{ii} = \frac{1}{a_{ii}}

Invert diagonal elementsBeginner
Orthogonal Matrix

A1=ATA^{-1} = A^T

Transpose the matrixBeginner

Common Mistakes to Avoid

Singular Matrices

Only matrices with det(A)0\det(A) \neq 0 have inverses. If det(A)=0\det(A) = 0, the matrix is singular and has no inverse.

Adjugate Signs

In the adjugate matrix, signs alternate: ++++ - + - + \ldots. Don't forget to apply (1)i+j(-1)^{i+j} for each cofactor.

Verification

Always verify that A×A1=IA \times A^{-1} = I and A1×A=IA^{-1} \times A = I. If not, there's an error in your calculation.

How to Calculate Matrix Inverses

Matrix inverse calculation involves systematic procedures for different matrix sizes using specific algorithms and verification methods.

A1=1det(A)adj(A)A^{-1} = \frac{1}{\det(A)} \text{adj}(A)

This is the general formula for matrix inverse using the adjugate method. The adjugate matrix is the transpose of the cofactor matrix.

Calculation Steps

1

Check Invertibility

Verify det(A) ≠ 0

2

Choose Method

Select appropriate method based on size

3

Calculate Inverse

Apply the chosen algorithm

4

Verify Result

Check that A × A^(-1) = I

Key Inverse Matrix Formulas

A1=1adbc(dbca)A^{-1} = \frac{1}{ad-bc} \begin{pmatrix} d & -b \\ -c & a \end{pmatrix}

adj(A)=CT\text{adj}(A) = C^T

AA1=A1A=IAA^{-1} = A^{-1}A = I

Examples

2×2 Matrix

A=[[1,2],[3,4]]A = [[1, 2], [3, 4]]

Steps:

  1. Calculate det(A) = 1×4 - 2×3 = -2

  2. Use adjugate formula

  3. A^(-1) = (1/-2) × [[4, -2], [-3, 1]]

A^(-1) = [[-2, 1], [1.5, -0.5]]

Diagonal Matrix

A=[[2,0],[0,3]]A = [[2, 0], [0, 3]]

Steps:

  1. For diagonal matrices

  2. Invert each diagonal element

  3. A^(-1) = [[1/2, 0], [0, 1/3]]

A^(-1) = [[0.5, 0], [0, 0.333]]

Identity Matrix

A=[[1,0],[0,1]]A = [[1, 0], [0, 1]]

Steps:

  1. Identity matrix is its own inverse

  2. I^(-1) = I

  3. No calculation needed

A^(-1) = [[1, 0], [0, 1]]

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Frequently Asked Questions

What is a matrix inverse?

A matrix inverse A1A^{-1} of a square matrix AA is a matrix such that AA1=A1A=IAA^{-1} = A^{-1}A = I, where II is the identity matrix. The inverse matrix allows us to "divide" by matrices and solve matrix equations.

When does a matrix have an inverse?

A square matrix has an inverse if and only if its determinant is non-zero (det(A)0\det(A) \neq 0). Such matrices are called invertible or non-singular. If det(A)=0\det(A) = 0, the matrix is singular and has no inverse.

How do I calculate the inverse of a 2×2 matrix?

For a 2×2 matrix A=(abcd)A = \begin{pmatrix} a & b \\ c & d \end{pmatrix}, the inverse is A1=1adbc(dbca)A^{-1} = \frac{1}{ad-bc} \begin{pmatrix} d & -b \\ -c & a \end{pmatrix}. First calculate the determinant, then apply the formula.

What is the Gauss-Jordan elimination method?

Gauss-Jordan elimination is a systematic method for finding matrix inverses. It involves augmenting the matrix with the identity matrix and performing row operations to transform the original matrix into the identity matrix, while the identity matrix becomes the inverse.

Can this calculator handle all matrix sizes?

Yes, our inverse matrix calculator can handle matrices of various sizes. For 2×2 matrices, it uses the direct formula. For larger matrices, it uses Gauss-Jordan elimination with step-by-step calculations.

Is this calculator free to use?

Yes, our inverse matrix calculator is completely free to use with no limitations. You can calculate inverses of as many matrices as you need.

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Last updated: 24/08/2025 — Written by the AskMathAI team