calculate-cotanx-2cotan-2x-then-simlify-k-0-n-1-2-k-tan-2-k-

Question Number 28609 by abdo imad last updated on 27/Jan/18

c a l c u l a t e c o t a n x - 2 c o t a n (2 x) t h e n s i m l i f y

\sum_{k = 0}^{n} \frac{1}{2^{k}} t a n (\frac{α}{2^{k}}) .