import numpy as np

# MULTIPLICATION
x = np.array(((2, 3), (3, 5)))
y = np.array(((1, 2), (5, -1)))
x * y
# => array([[ 2,  6], [15, -5]])
x = np.matrix(((2, 3), (3, 5)))
y = np.matrix(((1, 2), (5, -1)))
x * y
# => matrix([[17,  1], [28,  1]])

# CROSS PRODUCT
x = np.array([0, 0, 1])
y = np.array([0, 1, 0])

np.cross(x, y)
# => array([-1,  0,  0])

np.cross(y, x)
# => array([1, 0, 0])
