I have taken a circuit ‘A’. Voutput = Vinput*(e^(at)) for a constant input Vinput. But now when I try to cascade two such circuits.

How can I find the final output? My attempt was to find transfer function of ‘A’, TF= 1/(S-a). Since it was cascaded, final TF= 1/(S-a)^2. And inverse was found to be Voutput=Vinput * t *(e^(at)). This answer did not make sense because until t>1, output of cascade is smaller, also I am not sure if I can take transfer function like that.