A=as.matrix(data.frame(c(2,1), c(-3,4), c(0,2)))
A
B=as.matrix(data.frame(c(6,-1), c(1,0), c(-3,4)))
B
c=A+B
c

k=-1
k*A

B1=as.matrix(data.frame(c(3,-2,1), c(4,0,2)))
A%*%B1

A1=as.matrix(data.frame(c(1,3), c(2,1)))
det(A1)
solve(A1)
trA1 <- sum(diag(A1))
 trA1


A2=as.matrix(data.frame(c(1,-1,2), c(0,1,1),c(2,0,2)))
solve(A2)


A3=as.matrix(data.frame(c(1,9), c(4,1)))
eigen(A3)


A<-as.matrix(data.frame(c(3,2), c(2,3), c(2,-2)))
A
A.svd <- svd(A)
A.svd
u<-as.matrix(data.frame(c(1/sqrt(2),1/sqrt(2)), c(1/sqrt(2),-1/sqrt(2))))
u
l<-as.matrix(data.frame(c(5,0), c(0,3), c(0,0)))
l
v<-as.matrix(data.frame(c(1/sqrt(2),1/sqrt(18),2/3), c(1/sqrt(2),-1/sqrt(18),-2/3), c(0,4/sqrt(18),-1/3)))
v
u%*%l%*%v

A<-as.matrix(data.frame(c(1,2,2), c(2,1,2), c(2,2,1)))
 eigen(A)