The lower edge of a mural, which is 4 m high, is 2 m above an observer’s eye level, as shown in Figure 2.53. Show that the optical angle θ° is given by

where d m is the distance of the observer from the mural. See Review exercises Question 23.

Figure 2.53

Data from  Review exercises Question 23

Continuing Question 54 of Exercises 2.6.2, show that

and by applying the arithmetic–geometric inequality to

deduce that u° achieves its maximum value where d = 2√3.

Transcribed Image Text:

cos 0 = 12 + d [(4 + d)(36 + d)]