DANS LES POLYÈDRES 



[27] F^Mcos^-Nsin-^, /=Msm^H-Ncos^ 

 m — fA,, n~v, -■{m-^n) = A; A-h//.-h vr= o. 



139 



M 



r2 8jM=\ 



cos — (AP -H ^P' -H vP" -<- 3 A/) 



-t- cos -^ ( ;M,P -H vP' -H AP' ^- 3^1/) 

 -<-cos -^ ( vP -1- AP' -H yttP" -t- 3v/ ) 



— cos -^ ( AP H- vP' H- ^P" -H 3 A/) 



sin -^ ( f.p -H AP' -t- vP" ^ 3 A/] 



2t 



-N/ 



-^sin-^(^P-t-i/P' -»-AP"-H- 3ac/) 



-*- S™ "iJ- ( "P -*- ^P' -i-A(,P"-+-3v/) 

 -»- sm^( vP H-^P' ^- AP" -*- 3v/) 



2-T 



" sin-^(/*PH-AP' -*- vP"h-3^/) 

 sin -^ ( AP -H vP' -H i^P" -H 3 A/). 



