New posts in Trigonometry

sine vs Sine: understanding the differences

How do we know that the Sine function has no Non-Real Roots?

Proving $\sum_{k=1}^n\frac{\sin(k\pi\frac{2m+1}{n+1})}k>\sum_{k=1}^n\frac{\sin(k\pi\frac{2m+3}{n+1})}k$

Prove $\sum_{k=0}^n\binom{n}{k}\cos\left(\frac{k\pi}{2} - \frac{n\pi}{4}\right) = \sqrt{2^n}$

Show that $\angle PAB = \angle CAQ$

If sum of triangle angles is $180$ degrees, how $\sin(270)$ is possible?

Trigonometric functions -- sin - cos - tan - Differences, actual applications,

Wronskian of functions $\sin(nx), n=1,2,...,k$.

$\frac{\tan8°}{1-3\tan^2 8°}+\frac{3\tan24°}{1-3\tan^2 24°} + \frac{9\tan72°}{1-3\tan^2 72°} + \frac{27\tan216°}{1-3\tan^2 216°}=x\tan108°+y\tan8°$

If $x+y+z=xyz$, prove $\frac{2x}{1-x^2}+\frac{2y}{1-y^2}+\frac{2z}{1-z^2}=\frac{2x}{1-x^2}\times\frac{2y}{1-y^2}\times\frac{2z}{1-z^2}$