et loco poflerioris 



cof.iE'-^fin.(A-B)*-cof.iE'-i+cof.KA-B)S 

 hinc igitur fi breuitatis gratia loco 



cof. l A cof. i B 4- cof. I C cof. i D 



fcribatur Q, fiet 



Q (cof. I E* - fin. L ( A + Br) = cof. : A"" cof. l C cof. ^ D 

 4. cof l D' cof. ; A cof. -; B -h cof. ; C^ cof. ^ A cof ; B 



4-coi.;Vcor.iCcof.'D-cn;Ac.;B+cof;Acof;Bcf.?(A+B)» 



- cof i C cof ■ D + cof ■ C cof ; D cof. l (A + B)' 



— cof i A co(.-;b (cor:D'4-con: c^-i+cof '(a+b^)) 



-hcof.;CcoflD(cof.:A'+cof;B'--i+cof.;(A+B)'}. 



Atqui efl 



cof ; D"^ 4- cof lO-i=:\ (cof D + cof. C) 

 — cof i(D-i-C)cof -;(D-C); 



{imilique ratione 



cof. i A' -4- cof ; B' - 1 = ; (cof A -h cof B) 

 * nz cof KA -4- B) cof. i (A - B), 



tnmquc fiet 



cor.;Ccof;D(cof;A^+cof;B'-i+conKA+B)') 



=: cof ;C cof ,:D cof.; (A+B) (cof ; (A-B) + cof; ( A-B)) 



- 2 cof. ; A cof ; B cof -: C cof ^ D cof. ■ (A -+- B) 



A r T5 <;cor. ' ( A 4- B) cof ; (C - D ) ? . 

 =z cof : A cof , B ^^ ^^^j. . ( A + B) cof ; (C + D)S 



stcof ■Ccof:D=:cofUC-D)-i-cof ■ (C+-D)i 



hinc fubl^itutionc faifla, fiet 



cof 



