alt text
mat = matrix(c (1,3,2,4,1,3,1,0,1), ncol=3 , nrow=3, byrow=T) print(mat)
## [,1] [,2] [,3] ## [1,] 1 3 2 ## [2,] 4 1 3 ## [3,] 1 0 1
print(det(mat))
## [1] -4