Maple 2019 gives   
      
   int(exp(I*w*t)/(c+I*w),w=-infinity..infinity) assuming c>0   
      
           0   
      
   Next, when I tell it that t>0, it then gives   
      
   int(exp(I*w*t)/(c+I*w),w=-infinity..infinity) assuming c>0,t>0   
      
          2*Pi*exp(-c*t)   
      
   Which is correct.   
      
   Should it give zero for the first case?  With Mathematica 11.3   
      
   sol = Integrate[ConditionalExpression[Exp[I w t]/(c + I*w), c > 0],   
           {w, -Infinity,Infinity}]   
      
   gives   
      
   ConditionalExpression[(Pi*(1 + Sign[t]))/E^((c*t)/Sign[t]),   
             Element[t, Reals] && c > 0]   
      
   Which is zero, only when t<0 and  2*Pi*exp(-c*t) when t>0   
      
   So Maple and Mathematica agree when told t>0. But why Maple gives zero when   
   one does not tell it anything about if t is positive or not? Do you think this   
   is an OK result by Maple?   
      
   Thanks   
   --Nasser   
      
   --- SoupGate-Win32 v1.05   
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