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Math calculator

Nullspace Calculator

Right nullspace of a small real square matrix from RREF. Same engine as Linear System. Trivial kernel is {0}. Left-nullspace is a sibling. Runs locally.

Instant result
Result

Enter values to calculate.

Inputs
Mode
Formula
Trust summary Engine tested · Specification checked · 44/44 tests · Production surface contract 3/3 · v1.10.0
Input interpretation
Enter values to calculate.
Result
Model
A basis for ker A of a small real square matrix (order 2–4), with dim = n − rank.
Scope
Real square matrices
Verification
Engine tested · 44/44 tests · Production surface contract 3/3 · Specification checked · v1.10.0
Named expert review
Optional · Not performed
Specification basis
  • ISO 80000-2:2019 Quantities and units — Mathematics
Specification basis
Evidence
23 golden · 2 boundary · 19 property · Production surface contract 3/3 · Artifact integrity PASS
Production
Embedded snapshot: STALE · Last attested schema matched 1.10.0 snapshot / local build · Semantic contract ✓ · Last attestation PASS · current evidence changed · re-attestation required · Public/cache ✓ · Origin ✓ · Live production status STALE (1 capability; 163 remain CURRENT) @ 2026-09-19T00:00:17.039Z
Semantic contract
PASS

Formulas

Core equations used by this calculator.

Rank-nullitydim ker A = n − rank A
Free columnx_free = 1, x_pivot = −RREF row
iSquare matrices only, order ≤ 4. Reuses Gauss–Jordan already used by inverse, rank, and RREF. Not a CAS. Left-nullspace is /calc/math/left-nullspace. Float64. Pivot cutoff 10⁻¹⁵.

How to use

1

Enter a square matrix

2×2 or 3×3. Larger composition lives at /workspace/matrix. Rank and RREF are sibling discovery URLs.

2

Read the basis

A full-rank matrix returns {0}. Rank-deficient matrices return one vector per free column, with residual ‖Av‖.

Example calculations

Common configurations with formula and result.

ϟ

Rank 1

[[1,2],[2,4]]

dim = 1
[−2, 1]
ϟ

Identity

I₂

rank = n
{0}

Nullspace calculator specification

Version 1.10.0 · Engine tested

Calculation status

Review policy · Evidence

Definition
ker A = {x | Ax = 0}. This page is mode=nullspace on math.linear_algebra. Basis vectors come from RREF with free variables set to 1. Not a second engine. Left-nullspace is /calc/math/left-nullspace.
What it calculates
A basis for ker A of a small real square matrix (order 2–4), with dim = n − rank.
Inputs
  • order
  • a11…
Outputs
  • basis
  • dimension
  • rank
  • trivial
  • residual_max
Formula
dim ker A = n − rank A
Assumptions
  • Real square matrices
  • Order ≤ 4
  • Float64
  • Not a CAS
  • Not Jordan form as a product
Units
  • dimensionless
Boundary conditions
  • full rank → trivial kernel {0}
  • unknown mode (including jordan-form) → INVALID_MODE
Example
[[1,2],[2,4]] → basis [[-2,1]], dim=1
Validation cases

2 published on this page · 44/44 tests · Production surface contract 3/3 · View evidence

  • order=2 a11=1 a12=2 a21=2 a22=4 → dimension=1, basis=[[-2,1]]
  • mode=jordan-form order=2 a11=1 a12=0 a21=0 a22=1 → INVALID_MODE
Specification basis
  • ISO 80000-2:2019 Quantities and units — Mathematics
Calculation version
1.10.0
}

Frequently asked questions

Key distinctions behind the calculation.

Is this a second linear-algebra engine?

No. It is mode=nullspace on math.linear_algebra, the same engine as /calc/math/linear-system and /workspace/matrix. It reuses the RREF already used by /matrix-rref.

Does this return the left-nullspace or rowspace?

No. This seed is the right kernel. Rowspace is /calc/math/row-space. Left-nullspace (cokernel) is /calc/math/left-nullspace on this same engine.