f') of of of of j(x,

Equations (10.38) and (10.39) apply to the mth component of the complex Fourier series, Eq. (10.36). To ensure stability for a general property distribution, all components of Eq. (10.36) must be considered, and all values of Ax must be considered. This is accomplished by letting m vary from -00 to +00 and letting Ax vary from 0 to L. Thus, the product km Ax varies from -00 to +00.