Section 17
Determinants and inverses
2×2 determinant
intermedioviz
Oriented area scaling factor in 2D.
Cofactor expansion
intermedioviz
Expands a determinant along a row or column.
Determinant of a product
intermedioviz
The overall scaling factor multiplies under composition.
Invertibility criterion
intermedioviz
Characterizes invertible square matrices.
Inverse of a 2×2 matrix
intermedioviz
Inverts a nonsingular 2×2 matrix.
Cramer's rule
intermedioviz
Solves nonsingular square systems using determinants.