HP F2226A - 48GII Graphic Calculator User Manual page 508

2 2
Thus, c = 1/3, c = (π⋅i+2)/π , c = (π⋅i+1)/(2π ).
0 1 2
The Fourier series with three elements will be written as
g(t) ≈ Re[(1/3) + (π⋅i+2)/π 2 ⋅exp(i⋅π⋅t)+ (π⋅i+1)/(2π 2
)⋅exp(2⋅i⋅π⋅t)].
A plot of the shifted function g(t) and the Fourier series fitting follows:
The fitting is somewhat acceptable for 0<t<2, although not as good as in the
previous example.
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