class Vectors {

    public static Vector rotateAroundXAxis(Vector vector, double angle) {
        double cos = cos(angle);
        double sin = sin(angle);
        double y = vector.getY() * cos - vector.getZ() * sin;
        double z = vector.getY() * sin + vector.getZ() * cos;
        
        return vector.setY(y).setZ(z);
    }

}