923 
-2 = 
Cz (1 + a” °”) (l+e %/e - acto! cos wt,) 
Expending Eq- (I=-3lb), and substituting from the above triangle for cos wt 
and sin wt,: 
1/2 
=-2t,/@ =-t 
2F wO | lte pure o/ cos wt, 
k 2 1 + a” 9 
The relative response ¥ is therefore: 
woo | 1+ ear 2e7t0/® cos wt cs 
eres 2 (I-31le) 
2 1-+ w* 9 
8. Linear Rise to a Limiting Value - PF 
t, —> t 
F(t) = F(t/t,) H(t) - F(t/t,) H(t - t,) +F H(t - t,) 
t- t, 
= F(t/t.) H(t) - EF = H(t - to) (I-38) 
Substituting in Eqe (I-5), and solving as in Eq. (I-20): 
-108-= 
