View source for Orthogonality relation for cosine on (0,pi)

==Theorem==
The following formula holds for $m,n \in \{0,1,2,\ldots\}$ with $m\neq n$:
$$\displaystyle\int_0^{\pi} \cos(mt)\cos(nt) \mathrm{d}t=0,$$
where $\cos$ denotes [[cosine]].

==Proof==

==References==
* {{BookReference|An Introduction to Orthogonal Polynomials|1978|T.S. Chihara|prev=2cos(mt)cos(nt)=cos((m+n)t)+cos((m-n)t)|next=findme}} $(1.2)$

[[Category:Theorem]]
[[Category:Unproven]]