Solution 2.9.4.9 F(s)= A s + B s 2 + C s +1 : A = d ds s 2 F(s) j s=0 = d ds  s ; 1 s +1  j s=0 =  ;(s ; 1) (s +1) 2 + 1 (s +1)  j s=0 = 2 B = s 2 F(s) j s=0 =  (s ; 1) s +1  j s=0 = ;1: C = = (s +1)F(s)j s=;1 =  (s ; 1) s 2  j s=;1 = ;2: f(t)=[2; t ; 2e ;t ]1(t): 1