chapter  74
The complex or exponential form of a Fourier series
Pages 14

The form used for the Fourier series in Chapters 69 to 73 consisted of cosine and sine terms. However, there is another form that is commonly used-one that directly gives the amplitude terms in the frequency spectrum and relates to phasor notation. This form involves the use of complex numbers (see Chapters 23 and 24). It is called the exponential or complex form of a Fourier series.