Verify the Cayley-Hamilton theorem for A = [1 -1; 2 3]. Find the characteristic polynomial (p) and show that p(A) = 0.
a. p(λ) = λ² - 4λ + 5
b. p(λ) = λ² + 2λ - 5
c. p(λ) = λ² - 2λ - 5
d. p(λ) = λ² + 4λ - 5