638 



BELL SYSTEM TECHNICAL JOURNAL 



The first of these equations may be solved for 5i, the second for 62, 

 the third for 63, and so on, giving the following: 



82 = 



+ ^ T'arit - r) + T,x,(t - T) 



7^2 



+ \ r~a2it -T) + rM2(/ - T) 



/ r 1 



J"2 



i^ y + aaT + Ma 



(16) 



(17) 



53 = 



8i = 



<Pz(t) - n{t -T)- T<pz'{t - r) - 2 rV3"(/ - T) 



+ ^ r^aaC^ - r) + r/x3(/ - r) 



+ Tcx,{t -T)- TfjLy'it - r) + n,(t - T)\ 



+ 5i ( ^ rv2'"(/ -T)-'^ rwit - T) 



+ Ta^{t -T)- TiK^it - r) + M2(/ - T)\ 



+ 5i2 



^rv'"(^- r)+^r^/"(/- t) 



+ ^ r2a/'(/ - r) - Tcxat -T)+\ ai(/ - n 



+ ^rMi"(/-r)-Mi'(/-r)) 



+ 5,52 ii:r + aa +5i' 



K 



J^2 



A^y +rt«r + Ma 



(18) 

 (19) 



