from sympy import * 
x, y, z, t = symbols('x y z t') 
n = Matrix([[x, 1 / t], [t, x * x]])
copie = n * n
n = n + 3 * Matrix([[1, 0], [0, 1]])
n = pow(n,2)
n = n - copie
print(n)
print(simplify(n))