Spot the one that does not belong

Exercise and reference answers

Questions

1. Items

   1. |A| ≠ 0
   2. A is singular
   3. A⁻¹ exists

   Odd item

   A is singular

2. Items

   1. Minor
   2. Cofactor
   3. Adjoint

   Odd item

   Adjoint

3. Items

   1. a₁₁A₂₁ + a₁₂A₂₂ + a₁₃A₂₃
   2. a₁₁A₁₁ + a₁₂A₁₂ + a₁₃A₁₃
   3. |A| by expansion along R₁

   Odd item

   a₁₁A₂₁ + a₁₂A₂₂ + a₁₃A₂₃

Explanation