Can anyone help me with this hard trig. expression
95633
Help with this trigonometry problem
115128
How do I show this $\cos^2(\arctan(x))=\frac{1}{1+x^2}$
85571
How do I simplify $\sqrt{3}(\cot 70^\circ + 4 \cos 70^\circ )$?
107067
Finding the argument of $z=1-\cos(2\theta)-i\sin(2\theta)$
63155
Express $1+2\cos a$ as a product
126630
How to compute the integral of trigonometic function with multiple angle
18005
Angle notation for complex numbers in polar form
48956
Simplify $\arctan (\frac{1}{2}\tan (2A)) + \arctan (\cot (A)) + \arctan (\cot ^{3}(A)) $
60709
How do I get $\cos{\theta} \lt \frac{\sin{\theta}}{\theta} \lt 1$?
66872
Exact values of $\cos(2\pi/7)$ and $\sin(2\pi/7)$
33396
Generalizing a Trig Identity
89003
Finding a trigonometric polynomial
33100
Trigonomnetric equality involving tg
74143
Simplifying and evaluating $\cot 70^\circ+4\cos 70^\circ$
83332
Trig sum: $\tan ^21^\circ+\tan ^22^\circ+\cdots+\tan^2 89^\circ = \text{?}$
73512
Trigonometry Olympiad Question
42391
Calculate $\tan9^{\circ}-\tan27^{\circ}-\tan63^{\circ}+\tan81^{\circ}$