Sin(3 degrees) is close to 0 because it is the ratio of the opposite side over the hypotenuse. Imagine angle of 3 degrees forming a triangle. The opposite side would have to be very small in relation to the hypotenuse.
You have a typo in your cosine value. The cosine of 3 degrees is close to 1 not 0. Cosine is the relation of the adjacent side over the hypotenuse. In the same example above the adjacent side would be very similar to the hypotenuse. Thus giving a ratio of about 1.
