DATA 605 Week 2 Discussion

Page 278 C23

A <- matrix(c(1,3,2,4,1,3,1,0,1), nrow = 3, byrow = T)
A

##      [,1] [,2] [,3]
## [1,]    1    3    2
## [2,]    4    1    3
## [3,]    1    0    1

Hand On Solution with Factoring Mehtod

determinant_matrix <- A[1,1] * ((A[2,2] * A[3,3]) - (A[3,2] * A[2,3])) - 
  A[1,2] * ((A[2,1] * A[3,3]) - (A[3,1] * A[2,3])) +
  A[1,3] * ((A[2,1] * A[3,2]) - (A[2,2] * A[3,1]))

determinant_matrix

## [1] -4

R Solution

det(A)

## [1] -4