You are driving fast along the freeway, but you cannot see all about you! You have blind spots in your vision. So how do you find out where they are and what do you do about them?
Looking forwards, everything behind side on to you is invisible. You cannot rely on direct vision and must instead use mirrors. These side mirrors will reflect some of the picture for you but bits will be missing.
Each side mirror will give a field of view. To orientate yourself and view as much as possible, you need to align the side mirror to show part of the vehicle. However, this needs to be as little as possible because for all the area of the mirror showing your own vehicle, there is a part wasted which cannot see anything else.
Whatever you do, there will be an area outside the field of mirror, to your rear quarter or the area where another vehicle might be when it is coming by you.
Whilst stationary, you need to have someone walk around the car and take note of where you can see them and where not. You will find that as they come out from behind you (rear view mirror) they will pass through the side mirror vision area and out into invisibility before appearing in your normal direct vision.
Having noted this, you should ensure when driving that you allow for this blind spot. You can do that by allowing plenty of time for invisible vehicles to appear and by giving lots of notice of your movements.
You can also make a small movement of the head to give a different angle of direct vision. This will cut down the overall blind spot but of course means taking your eyes off the road in front.