# C24 278


A = matrix(c(-2, -4, 2, 3, -2, 4, -2, 1, 2), ncol = 3, nrow = 3)
A

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

det(A)

## [1] 70

det_A = (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[3,1] * A[2,2])))

det_A

## [1] 70

#M10 278

# A =matrix(c(2,3,4,k), ncol = 2, nrow = 2)
#|A|=2k-12=0
#k=6
A =matrix(c(2,3,4,6), ncol = 2, nrow = 2)
det(A) #K=6 

## [1] 0