Discussion 2

Compute the determinant of the matrix

Reading question 2 Page 352

\[\mathbf{det} = \left[\begin{array} {rrr} 2 & 3 & -1 \\ 3 & 8 & 2 \\ 4 & 1 & 3 \end{array}\right] \]

\[\mathbf{2*det} = \left[\begin{array} {rrr} 8 & 2 \\ 1 & 3 \\ \end{array} \right] \]

a = 8*3-2*1
a

## [1] 22

\[\mathbf{-3*det} = \left[\begin{array} {rrr} 3 & 2 \\ 4 & 3 \\ \end{array} \right] \]

b = 3*3-2*4
b

## [1] 1

\[\mathbf{-1*det} = \left[\begin{array} {rrr} 3 & 8 \\ 4 & 1 \\ \end{array} \right] \]

c = 3*1-8*4
c

## [1] -29

Final solution

2*a-3*b-1*c

## [1] 70