import math


def rotate_vector(vector, angle_degree):
    """Rotate a vector with given angle in degree."""
    angle_rad = math.pi * angle_degree / 180
    xval = vector[0]*math.cos(angle_rad) + vector[1]*math.sin(angle_rad)
    yval = -vector[0]*math.sin(angle_rad) + vector[1]*math.cos(angle_rad)
    return xval, yval