Inverse matrix definition

A square matrix A has an inverse A^{-1} exactly when its determinant is nonzero, and multiplying A by its inverse on either side gives the identity matrix. It is used to define and test invertibility in linear algebra.

\boldsymbol{A}\boldsymbol{A}^{-1}=\boldsymbol{A}^{-1}\boldsymbol{A}=\boldsymbol{I},\quad \det \boldsymbol{A}\neq 0

What the symbols mean

square matrix
inverse of the matrix \boldsymbol{A}
identity matrix of the same size as \boldsymbol{A}
determinant of \boldsymbol{A}

About this formula

  • FieldMathematics
  • TopicLinear algebra
  • LevelUniversity
  • Also calledmatrix inverse, inverse of a square matrix, inverse of a matrix, A times A inverse equals identity, invertible matrix condition, matrix inverse determinant nonzero
  • SourceWikidata Q17123743

Write it in Obsidian

MathLive is a free visual math editor for Obsidian. Run Find a formula, type “inverse matrix definition”, and it goes into your note as editable LaTeX. You can also scan formulas from screenshots, PDFs and handwriting.

Related formulas