Thanks a lot for your help. But I don't understand "RCLF", what this?? I looked the flag :Radians,Decimal, Real, Approximate and Rigorous Off. And it's ok. And I've the other post, and it's about Fourier series, but I think my problem is not a problem specific to the Fourier series, but more about sum.
Message
Re: Fourier series
2008-05-18 by OLLIVIER