a) You wish to have a plane pocket mirror that is as discreet as possible but with which you can see the whole width of your face. If your face is 23.0 cm wide, what is the minimum width, in cm, of the mirror for you to be able to see the whole width of your face in one eye?
b) What would be the minimum width of the mirror if you are willing to accept that you must use two eyes to see the full width of your face? (Take the distance between the centers of your eyes to be 6.60 cm.)
I know that for a plane mirror the height needs to only be half the height of the person, but I haven't learned about width.
The Attempt at a Solution
I think part a's answer is 11.5 cm because that is half the width of the face and for the height you only need half the distance, but I don't know if that's right