How can I prove $\arctan x  0$
103757
how can I prove that $\frac{\arctan x}{x }< 1$?
60559
How prove this $x^3<\sin^2{x}\tan{x},x\in\left(0,\dfrac{\pi}{2}\right)$
95673
General formula for $\sin\left(k\arcsin (x)\right)$
617
Find θ: $β=\arctan\frac{(R+r)·\sin(θ)-r·\sin(θ(1+\frac{R}{r}))}{(R+r)·\cos(θ)-r·\cos(θ(1+\frac{R}{r}))}$
147410
ArcTan(2) a rational multiple of $\pi$?
50019
Prove $0$ is a partial limit of $a_n$
158210
showing $\arctan(\frac{2}{3}) = \frac{1}{2} \arctan(\frac{12}{5})$
79686
How can I prove these statements?
105852
How to verify whether or not there exists a vector $x$ such that $Ax > 0$?
31379
Relationship between $\tanh x$ and $\arctan x$
18473
Proof for the formula of sum of arcsine functions $ \arcsin x + \arcsin y $
53307
how to strictly prove $\sin x<x$ for $0<x<\frac{\pi}{2}$
66451
In a ring, how do we prove that a * 0 = 0?
150321
How do you prove Cov $\left( \bar{X} , X_i - \bar{X} \right) = 0$?
4573
Explicitly finding the sum of $\arctan(1/(n^2+n+1))$
79213
Proof about a Topological space being arc connect
102932
Integral $\int_0^\infty \frac{\arctan(x) dx}{x(1+x^2)}$?