Happens always to me, the pasted link doesn't work.   
   But one can type in the problem, and will get a solution.   
   But they don't do the step and replace e^c0 by a new constant.   
      
   Am Dienstag, 15. August 2017 21:04:58 UTC+2 schrieb burs...@gmail.com:   
   > Solve |y′ + y cos(t) = 0 |   
   >    
   > Compare this to here (you need to click on show    
   > steps, in the grey areas, to see all steps):   
   > https://www.symbolab.com/solver/step-by-step/y'%20%2By%20cos/l   
   ft%28t/right%29%20%3D%200   
      
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