# Question:Simplification of preexponential terms after convolution

## Question:Simplification of preexponential terms after convolution

Maple
Dear all, i want to do some pharmacokinetic calculations with the convolution intergral. E.g. the input rate into the linear system is Inpfunc:=t-> a*exp(-k*t)+b*exp(-m*t); the system impulse response is Transfunc:=t->c*exp(-u*t)+d*exp(-v*t)+e*exp(-w*t); When i compute the system response to the input rate function as Respf:=int(Transfunc(t-tau)*Inpfunc(tau),tau=0..t); I do obtain a huge mess of exponentials. With the 'collect' function i collected the preexponential terms but they were still huge (abt. 4 screens full). I have tried 'factor', 'symplify' and so on but all commands failed to give the correct solution which should be a sum of 5 exponentials with simple preexponential terms like a * (c / (u - k) + d / (v - k) + e / (w - k)) which is the coefficient for exp(-k*t). Please help me to get simple solutions. Thanx in advance Martin from Neuenburg, Germany
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