Determinant (3x3) Cofactor Expansion - Matrix to Formula (Single Term)

Question

Using cofactor expansion along the first row, which shows the fully expanded determinant calculation?

$$\left[ {\begin{array} {ccc}  0 &  1 &  -1 \ -6 &  -5 &  9 \ -6 &  -5 &  1 \end{array}  } ight]$$

Accepted Answer

$$0 \cdot (-5 \cdot 1 - 9 \cdot -5) - 1 \cdot (-6 \cdot 1 - 9 \cdot -6) + -1 \cdot (-6 \cdot -5 - -5 \cdot -6)$$

Answer

$$0 \cdot (-5 \cdot 1 - -5 \cdot 9) - -6 \cdot (1 \cdot 1 - -5 \cdot -1) + -6 \cdot (1 \cdot 9 - -5 \cdot -1)$$

Answer

$$0 \cdot (-7 \cdot 1 - 9 \cdot -5) - 1 \cdot (-6 \cdot 1 - 9 \cdot -6) + -1 \cdot (-6 \cdot -5 - -7 \cdot -6)$$

Practice: Matrices - Determinant (3x3) Cofactor Expansion - Matrix to Formula (Single Term)