Thursday, September 3, 2015

trigonometry - How to prove this quasi-geometric trigonometric series identity without induction

2sinxn1r=1sinrxcos[(nr)y]cos(nx)cos(ny)cosxcosysin(nx)sinx



The identity can be tediously proven using the Axiom of Induction.



I am looking for other means of proving this identity.

No comments:

Post a Comment

analysis - Injection, making bijection

I have injection f:AB and I want to get bijection. Can I just resting codomain to f(A)? I know that every function i...