Is there any way to simplify the product of cosines?
59003
Product of cosines: $ \prod_{r=1}^{7} \cos \left(\frac{r\pi}{15}\right) $
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
99843
How to simplify $ \sum_{k=0}^{\infty} \binom{k + r - 1}{k} x^k$
58958
How to understand dot product is the angle's cosine?
115090
Alternative definition of hyperbolic cosine without relying on exponential function
121319
Why do I get a converging result when pressing cosine multiple times on a calculator?
74294
How to simplify $\sum_{i=1}^{k}\binom{n + i - 1}{i}$?
13186
Approximating cos(43) with error less than $8/60000$
124897
How many ways are there to define sine and cosine?
75457
How do i simplify the following: $\sum_{i=1}^n (3i^2+4) - \sum_{j=2}^{n+1} (3j^2+1)$
15985
simplify $(a_1 + a_2 +a_3+... +a_n)^m$
47985
How can I break equations in smaller pieces?
12841
Ratio of sines given, find ratio of cosines?
9479
$\sum \cos$ when angles are in arithmetic progression
98653
Easiest way to solve $y''+y=\frac{1}{\cos x}$
35765
product of two numbers ending in 6 also ends with 6
17188
Simplify $\cos(n \pi)$ and $\sin(n \pi)$ when n is an integer