Matrix Calculator

Perform matrix operations with interactive input
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Result

Select an operation and enter matrix values to see the result.

Complete Matrix Operations Guide

What is a Matrix?

A **matrix** is a rectangular array of numbers, symbols, or expressions arranged in rows and columns. Matrices are fundamental tools in linear algebra and are extensively used in computer graphics, physics simulations, economics, engineering, and data science.

Matrix Notation:

A matrix with m rows and n columns is called an m×n matrix. Each element is typically denoted as aij where i is the row number and j is the column number.

Matrix Operations Explained

1. Matrix Addition & Subtraction

Two matrices can be added or subtracted only if they have the same dimensions. The operation is performed element-wise: (A ± B)ij = Aij ± Bij

2. Matrix Multiplication

Matrix A (m×n) can be multiplied by matrix B (n×p) only if the number of columns in A equals the number of rows in B. The result is an m×p matrix. This operation is NOT commutative (A×B ≠ B×A).

3. Determinant

The determinant is a scalar value that can be computed from a square matrix. It provides important information about the matrix, such as whether it's invertible (det ≠ 0) and the volume scaling factor for linear transformations.

4. Matrix Inverse

The inverse of a square matrix A is denoted A⁻¹. It exists only if det(A) ≠ 0. The inverse satisfies: A × A⁻¹ = A⁻¹ × A = I (identity matrix).

5. Transpose

The transpose of a matrix A, denoted Aᵀ, is obtained by swapping rows and columns. If A is m×n, then Aᵀ is n×m. Element (Aᵀ)ij = Aji.

Real-World Applications

  • Computer Graphics: 3D transformations (rotation, scaling, translation) use matrix multiplication
  • Machine Learning: Neural networks rely heavily on matrix operations for forward and backward propagation
  • Physics: Quantum mechanics uses matrices to represent states and operators
  • Economics: Input-output models and linear programming use matrix algebra
Quick Tips
  • Identity Matrix
    A square matrix with 1s on the diagonal and 0s elsewhere. Acts like "1" in multiplication.
  • Singular Matrix
    A square matrix with determinant = 0. It has no inverse and represents a "degenerate" transformation.
  • Symmetric Matrix
    A matrix that equals its transpose (A = Aᵀ). Common in physics and statistics.
Common Matrix Sizes
  • 2×2: Simple transformations, basic linear systems
  • 3×3: 3D graphics, rotation matrices
  • 4×4: Homogeneous coordinates in computer graphics
  • n×n: General linear systems and eigenvalue problems

Frequently Asked Questions

Matrix multiplication requires the number of columns in the first matrix to equal the number of rows in the second matrix. This is because each element in the result is computed as a dot product of a row from the first matrix and a column from the second matrix.

A singular matrix has a determinant of zero and cannot be inverted. Geometrically, it represents a transformation that collapses space into a lower dimension (e.g., squashing a plane into a line).

In 3D graphics, transformation matrices (4×4) are used to rotate, scale, and translate objects. Multiple transformations can be combined into a single matrix through multiplication, making rendering very efficient.

A row vector is a 1×n matrix (one row, n columns), while a column vector is an n×1 matrix (n rows, one column). They represent the same data but are used differently in matrix multiplication.

Linear Algebra Basics

Matrices are the foundation of linear algebra. Understanding matrix operations is essential for advanced mathematics, computer science, and engineering applications.

Matrix Properties
Commutative? Addition: ✓ Yes
Multiplication: ✗ No
Associative? Both: ✓ Yes
Distributive? A(B + C) = AB + AC ✓
Pro Tip

When solving systems of linear equations, you can represent them as a matrix equation Ax = b, where A is the coefficient matrix, x is the variable vector, and b is the constant vector. The solution is x = A⁻¹b (if A is invertible).