Thus,

c0 = 1/3, c1 = (π⋅i+2)/π2, c2 = (π⋅i+1)/(2π2).

The Fourier series with three elements will be written as

g(t) ≈ Re[(1/3) + (π⋅i+2)/π2⋅exp(i⋅π⋅t)+ (π⋅i+1)/(2π2)⋅exp(2⋅i⋅π⋅t)].

Reference

For additional definitions, applications, and exercises on solving differential equations, using Laplace transform, and Fourier series and transforms, as well as numerical and graphical methods, see Chapter 16 in the calculator’s user’s guide.

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