from math import cos, sin
import numpy as np
theta = np.deg2rad(30)
rot = np.array([[cos(theta), -sin(theta)], [sin(theta), cos(theta)]])
v = np.array([1, 0])
w = np.array([3, 4])
v2 = np.dot(rot, v)
w2 = np.dot(rot, w)
print(v2) # [0.8660254 0.5 ]
print(w2) # [0.59807621 4.96410162]