How to prove that $\tan^{-1}(x)+\tan^{-1}(\dfrac{1}{x})=\pi/2$?
11059
Verify the identity: $\tan^{-1} x +\tan^{-1} (1/x) = \pi /2$
150843
Evaluation of $\int_0^{\pi/4} \sqrt{\tan x} \sqrt{1-\tan x}\,\,dx$
21855
Prove $\sum_{n=1}^{\infty}\arctan{\left(\frac{1}{n^2+1}\right)}=\arctan{\left(\tan\left(\pi\sqrt{\frac{\sqrt{2}-1}{2}}\right)\cdots\right)}$
97326
Find $\lim_{x \to 0} (\frac{\tan(x)}{x})^{\frac{1}{x}}$
153867
Evaluate $ \int_{0}^{\frac{\pi}2}\frac1{(1+x^2)(1+\tan x)}\:\mathrm dx$
123920
How prove this inequality $\tan{(\sin{x})}>\sin{(\tan{x})}$
137376
Proving a trig identity: $\frac{\sin(A + B)}{\sin(A - B)}=\frac{\tan A + \tan B}{\tan A - \tan B}$
46353
Proof that $\cos(\pi/3)=1/2$
127759
Prove that $\frac{\sin(a)}{\sin(b)} < \frac{a}{b} < \frac{\tan(a)}{\tan(b)}$ where $0 < b < a < \frac{\pi}{2}$
154172
Finding $\tan t$ if $t=\sum\tan^{-1}(1/2t^2)$
28771
Prove that $\int_{0}^{1}\sin{(\pi x)}x^x(1-x)^{1-x}\,dx =\frac{\pi e}{24} $
43184
Using the Residue Theorem to Prove that $\int^{2\pi}_{0} \frac{1}{(a+\cos\theta)^{2}} d \theta=\frac{2\pi a}{(a^{2}-1)^{3/{2}}}.$
60559
How prove this $x^3<\sin^2{x}\tan{x},x\in\left(0,\dfrac{\pi}{2}\right)$
48651
Prove that $\int_0^1t^{p-1}(1-t)^{q-1}\,dt=\frac{\Gamma(p)\Gamma(q)}{\Gamma(p+q)}$ for positive $p$ and $q$
64497
prove that $\tan(\alpha+\beta) = 2ac/(a^2-c^2)$
12741
How to prove that: $\tan(3\pi/11) + 4\sin(2\pi/11) = \sqrt{11}$
151127
Confirm that $\int_{0}^{\infty}t^{-1}\sin t dt=\pi/2$