- #1
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Homework Statement
Maybe I'm just blind, but how is
[tex]T_n(x)=\left(\frac{1+\cos(t-a)}{b}\right)^n[/tex]
of the form
[tex]T_n(x)=\sum_{k=-n}^nc_ke^{ikx}[/tex]
?
I can get
[tex]\left(\frac{\cos(t-a)}{b}\right)^n[/tex]
by setting
[tex]c_{\pm n}=\left(\frac{e^{\mp ia}}{2b}\right)^n[/tex]
and the rest of the c_k= 0, but how does the +1 comes in?
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