i3a, 



-/> je-4t>-+i3 x 2 6 lo 4 f — = r a: 3 « 



/ l'(i — x+)' 4 • S • lii • • ■ 4P J \'(i — x^) 



_, l 4f^ !?:;;:« 4f>-':> y4f>-'4 ,1 4f>-2 4p-fi ig 6-î.2-I_i_P 



4(p-3}' 4P •4?-4-4p-8^ "' ^4" 4? ' 4Ï>-4 " * " * ï^^ " 8 ~^ -l "^ '^• 



duo jarn intégrale f Yi~4r^ dcteiminemas , statuamus 



dz 



77T-- — n =^ z^ ., liinc d x zn ï — ; :: 



"^^'-"'^ "V î^ / (1 + ^^) v'' (l + z^)' 



q^^are /^^^^ = /^i^ = z ^ .z: ^ /^ = ^ Arc. 

 tang. z ziz ï Ave. tang. y '^^ . Siibstituto hoc valore in ex- 

 pressione praecedente, prodibit hoc intégrale : 



•X4P-+-' dx „ . j- 4f — • 



r x^^^- d;e — 2 6 lo tLi^f i Arc tanf? ——- 



^P'~^ -1 4f — - ^,4P — 6 ;! 4P— 2 4P— 6 4f— 10 



V{i — x4) 4 • 8 ' 12 ••■••• • 4P 2 b*y(, x4) 



»' V ''L 4P 4(P— 4f 4(P — =J 4P 4P— 4 



1 4p-^ 4P-6 4P:iLr^4p-'4 .1 iP^ 4l>^ 10 6-r21_L^rnncf 



"^4C^-3)• 4P •4P-4-4P-8^ ^^ 4P ' 4^-4 - î^ ' S ^ J "^'-OnSt. 



§. iS. lïaec ad illcisti-andam soliitionem §. 7. siiiTi- 

 cieut. Quo auteni praestantia methodi a nohis traditae 

 ulterius eluceat, alias séries, ab illa^ qiia hucusqiie usi 

 sumus, diversas, consideremus, quein in finem sequentia 

 sol venins problcmata. 



P r ohl em CL 



§. 19. Intégrale /^^f^-^^[°J^ = °] extensum ab illust. 

 L. Eulero*) =r — ^ log. 2 exhibituni est, dénotante tt pe- 



*) V. Acta Acad. Imp. Petrop. T. i. P. II. De Integratione fbrmulae 

 y >~(,Jir;^) ladx=zJ extensa. Auct. U tulero. 



17'^ 



