DANS LES POLYÈDRES. 437 



^ JFçsin[/Ô/5-sin(9-i- J)]-H/5'cos[/ô/Jsin(?-H - \^ 



sin S/ÔcosUh--]! zz 0, 



{F?sin[/9/Fsin(o- J )]+>cos[/ô/3-sin(,^- 1 )]| 



sinr 3/6eos(<p— l]"] — 0, 



[211 / i^'P^'"[^V3'sin<p]— /?cos[/9/5Tsm(p]]sin[3/Ôcos?>J = 0, 

 j F?cos[/ô/7sin(<p-»-l)]-/çsm[/Ô/i-sin(ç-t-l)]j 



sinl 3/ôcosU-)--jl — 0, 

 j F?cos[/9/Isin(ç- 1 )]-/?sin[/9/^sin(^ J )]) 



sin 3 /9cosf (p— - ) I = , 

 jF(pcos[/9/Fsin(p] -4-y9sin[/9/3'sin?)]jsin[3/9coS(i>] rz 0. 



[22] sin[3/9cos(T.-t-ljl= 0, sinr3/9cos(?— I]] = 0, 



sin[3/9cos(p] =r 0. 



[23] 3/9cos^,p-H jj = mTT, 3/9cos(9— -] = n-TC. 



^ 3 /9 cos ^<p-i- ^ j = ffivr , "1 / /Ô/J-sin, 



tangcj) m 



[24]/3/9cosUl)=:;^7r,) / -/ 



f-9 



^~3Vi'^^("+'")'+(''-'")' 'i 



I ^9/3 sin 



^3/ôcos9 zr (m-\-n)7r.l I =-^{«+2'»). 



