The Fourier cosine coefficient an for the function f(x) = \(\left\{\begin{array}{c}c−x ; 0 is:
1
\(\frac{c}{n^{2} π^{2}}\)[1 − cos n π]
2
\(\frac{2 c}{n^{2} π^{2}}\)[1 − cos n π]
3
\(\frac{2 c^{2}}{n^{2} π^{2}}\)[1 − cos n π]
4
\(\frac{4 c}{n^{2} π^{2}}\)[1 − cos n π]