Function Fourier - HP F2226A - 48GII Graphic Calculator User Manual

Thus, the first three terms of the function are:
f(t) ≈ 1/3 – (4/π 2
)⋅cos (π⋅t)+(2/π)⋅sin (π⋅t).
A graphical comparison of the original function with the Fourier expansion
using these three terms shows that the fitting is acceptable for t < 1, or
thereabouts. But, then, again, we stipulated that T/2 = 1. Therefore, the
fitting is valid only between –1 < t < 1.

Function FOURIER

An alternative way to define a Fourier series is by using complex numbers as
follows:
2 in π t
f ) ( t c exp( ),
n
T
n
where
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