# Problem 16:
# 
A = matrix(c(5, -1, 3, 1), nrow=2, ncol=2, byrow=T)
print(eigen(A))

# Problem 17:
# 
A = matrix(c(3, -2, 4, -1), nrow=2, ncol=2, byrow=T)
print(eigen(A))

# Problem 18:
# 
A = matrix(c(-2, 1, 1, -2), nrow=2, ncol=2, byrow=T)
print(eigen(A))

# Problem 19:
# 
A = matrix(c(1, complex(r=0, i=1), -complex(r=0, i=1), 1), nrow=2, ncol=2, byrow=T)
print(eigen(A))

# Problem 20:
# 
A = matrix(c(1, sqrt(3), sqrt(3), 1), nrow=2, ncol=2, byrow=T)
print(eigen(A))

# Problem 21:
# 
A = matrix(c(-3, 3/4, -5, 1), nrow=2, ncol=2, byrow=T)
print(eigen(A))

# Problem 22:
# 
A = matrix(c(1, 0, 0, 2, 1, -2, 3, 2, 1), nrow=3, ncol=3, byrow=T)
print(eigen(A))

# Problem 23:
# 
A = matrix(c(3, 2, 2, 1, 4, 1, -2, -4, -1), nrow=3, ncol=3, byrow=T)
print(eigen(A))

# Problem 24:
# 
A = matrix(c(11/9, -2/9, 8/9, -2/9, 2/9, 10/9, 8/9, 10/9, 5/9), nrow=3, ncol=3, byrow=T)
print(eigen(A))

# Problem 25:
# 
A = matrix(c(3, 2, 4, 2, 0, 2, 4, 2, 3), nrow=3, ncol=3, byrow=T)
print(eigen(A))

# Problem 28:
# 
A = matrix(c(1, -2, 3, -1, 1, -2, 2, -1, 3), nrow=3, ncol=3, byrow=T)
print(det(A))