Simplifying Trig Product in terms of a single expression and $n$
32792
Proving: $\cos A \cdot \cos 2A \cdot \cos 2^{2}A \cdot \cos 2^{3}A ... \cos 2^{n-1}A = \frac { \sin 2^n A}{ 2^n \sin A } $
146047
Proving that $\cos(2\pi/n)$ is algebraic
39957
Product of binomial coefficient as a basis
34374
Simplifying factorials: $\frac{(n-1)!}{(n-2)!}$
89003
Finding a trigonometric polynomial
34637
Evaluating $\sum\frac{\sin(n)}{n^a}$
482
Express $1 + \frac {1}{2} \binom{n}{1} + \frac {1}{3} \binom{n}{2} + \dotsb + \frac{1}{n + 1}\binom{n}{n}$ in a simplifed form
13297
Prove the following trigonometric identity without a calculator involved
114418
A deduction from $x^n-1=(x^2-1)\prod_{k=1}^{(n-2)/2}[x^2-2x\cos{\frac{2k\pi}{n}}+1]$
109760
Showing that the product of all $n$th Roots of Unity is $(-1)^{n+1}$
33100
Trigonomnetric equality involving tg
127380
Use vectors to prove $\cos(\beta - \alpha) = \cos \alpha \cos\beta + \sin\alpha \sin\beta$
48956
Simplify $\arctan (\frac{1}{2}\tan (2A)) + \arctan (\cot (A)) + \arctan (\cot ^{3}(A)) $
60256
Is there a way to get trig functions without a calculator?
68725
Find expression for : $ S_n =\sum_{i=1}^{n} \frac{i}{i^4+i^2+1} $
84775
How to evaluate $\det (1+x_iy_j)_{n\times n}$?
51842
Simplify $\prod_{k=1}^5\tan\frac{k\pi}{11}$ and $\sum_{k=1}^5\tan^2\frac{k\pi}{11}$