Introduction
In this Section we address the following problem:
Can we find a Fourier series expansion of a function defined over a finite interval?
Of course we recognise that such a function could not be periodic (as periodicity demands an infinite interval). The answer to this question is yes but we must first convert the given nonperiodic function into a periodic function. There are many ways of doing this. We shall concentrate on the most useful extension to produce a socalled halfrange Fourier series .
Prerequisites
 know how to obtain a Fourier series
 be familiar with odd and even functions and their properties
 have knowledge of integration by parts
Learning Outcomes

choose to expand a nonperiodic function either as a series of sines or as a series of cosines
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