MathematicsLinear Algebra and TransformationsA-Level

Rotation Matrix (2D) Calculator

This matrix performs a counter-clockwise rotation of a point or vector in 2D Cartesian space by an angle θ about the origin.

Use the free calculatorCheck the variablesOpen the advanced solver
This is the free calculator preview. Advanced walkthroughs stay in the app.
Result
Ready
Rotation Angle

Formula first

Overview

The matrix operates on a column vector by multiplying it to transform coordinates while preserving the origin's position and the lengths of vectors. It is a fundamental component of linear transformations, illustrating how geometric operations are expressed as algebraic matrix operations.

Symbols

Variables

= Rotation Angle, x = Initial X-coordinate, y = Initial Y-coordinate

Rotation Angle
Variable
Initial X-coordinate
Variable
Initial Y-coordinate
Variable

Apply it well

When To Use

When to use: Apply this when you need to find the new coordinates of a point after it has been rotated by a specific angle around the origin.

Why it matters: It is essential in computer graphics, game engine development, and robotics for calculating the orientation and movement of objects in 2D space.

Avoid these traps

Common Mistakes

  • Swapping the positions of sine and cosine components.
  • Incorrectly placing the negative sign on the sine in the wrong row or column.
  • Mixing up degrees and radians when performing calculations.

One free problem

Practice Problem

Rotate the point (1, 0) counter-clockwise by 90 degrees. What is the new x-coordinate?

Rotation Angle90
Initial X-coordinate1
Initial Y-coordinate0

Solve for:

Hint: Use cos(90) = 0 and sin(90) = 1 in the rotation matrix formula.

The full worked solution stays in the interactive walkthrough.

References

Sources

  1. Stewart, J. (2015). Calculus: Early Transcendentals.
  2. Strang, G. (2016). Introduction to Linear Algebra.
  3. A-Level Mathematics Specification: Further Pure Mathematics (Matrices and Transformations)