Prove that $ \tan40° + \sqrt 3 =4 \sin40° $
74143
Simplifying and evaluating $\cot 70^\circ+4\cos 70^\circ$
63679
Picture/intuitive proof of $\cos(3 \theta) = 4 \cos^3(\theta)-3\cos(\theta)$?
9539
$\alpha$ and $\beta$ are solution of $a \cdot \tan\theta + b \cdot \sec\theta = c$ show $ \tan(\alpha + \beta) = \frac{2ac}{a^2 - c^2}$
30600
Why does $\tan^{-1}(1)+\tan^{-1}(2)+\tan^{-1}(3)=\pi$?
1210
Write an expression for $(\cos θ + i\sin θ)^4$ using De Moivre’s Theorem.
142673
Evaluate $\tan^{2}(20^{\circ}) + \tan^{2}(40^{\circ}) + \tan^{2}(80^{\circ})$
44247
For $a^3+b^3+c^3=3$ prove that $a^4b+b^4c+c^4a\leq3$
87682
Show that $\sqrt{2}\notin \mathbb{Q}(\sqrt[4]{3})$
58932
Hard contest type trigonometry proof
123920
How prove this inequality $\tan{(\sin{x})}>\sin{(\tan{x})}$
28347
Prove that $\sqrt 2 + \sqrt 3$ is irrational
120953
Show that, $2\arctan\left(\frac{1}{3}\right)+2\arcsin\left(\frac{1}{5\sqrt2}\right)-\arctan\left(\frac{1}{7}\right)=\frac{\pi}{4}$
7966
How prove $ \sqrt{2}+\sqrt{3}>\pi$?
68881
Solve for $\theta$: $a = b\tan\theta - \frac{c}{\cos\theta}$
106355
How to prove Lagrange trigonometric identity
54512
How do I prove: $\cos (\theta + 90^\circ) \equiv - \sin \theta $
52311
Prove that $0 \le \frac{1+\cos\theta}{2+\sin\theta} \le \frac{4}{3}$ for all real $\theta$.