Chapter 13, Problem 13.5P

Consider the two parallel, coaxial, ring−shaped disks shown schematically.

Show that $F_{12}$ can be expressed as
$F_{12}=\frac{1}{A_1}\left\{A_{(1,3)}{F}_{(1,3)(2,4)}-A_3{F}_{3(2,4)}-A_4(F_{4(1,3)}-F_{43})\right\}$ where all view factors on the right−hand side of the equation can be evaluated from Figure 13.5 or Table 13.2 for coaxial parallel disks.