From: rouben@x301-1.   
      
   In article <84fdfdbe-d1f6-4693-8faa-8ba283372e71@googlegroups.com>,   
   acer   wrote:   
   >restart;   
   >integrand := cos(x)* sin(x)^2*cos(n*x):   
   >int(integrand,x=0..2*Pi,allsolutions) assuming n::integer, n>0;   
   >   
   >                     /  1   
   >                     |  - Pi         n = 1   
   >                     |  4   
   >                     |   
   >                    <    1   
   >                     | - - Pi        n = 3   
   >                     |   4   
   >                     |   
   >                     \   0         otherwise   
   >   
      
   Let's look at a simpler case:   
   restart;   
   > kernelopts(version);   
              Maple 2017.3, X86 64 LINUX, Sep 27 2017, Build ID 1265877   
      
   > int(cos(n*x), x=0..2*Pi, allsolutions) assuming n::integer;   
                               { 2 Pi          n = 0   
                               {   
                               {  0          otherwise   
      
   That's good. But this one doesn't work -- the n=0 case should give 2 Pi:   
   > int(exp(n*I*x), x=0..2*Pi, allsolutions) assuming n::integer;   
                                          0   
      
   --   
   Rouben Rostamian   
      
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