# Américo Tavares

Queluz, Portugal

problemasteoremas.wordpress.com

Age: 62

I'm a retired Portuguese electrical engineer.

You can contact me at acltavares[at]sapo[dot]pt

MathOverflow account

 31s reviewed Approve suggested edit on How is $(\arg F)(z)$ of complex function calculated? 1h revised Find the volume using triple integralsAdded (integral) tag; fixed two spelling typos 1d revised How can evaluate $\lim_{x\to0}\frac{3x^2}{\tan(x)\sin(x)}$?added 116 characters in body 1d reviewed Approve suggested edit on An integer $n$, such that $nx = 0$, where $x$ belongs to the quotient group $\Bbb Q/\Bbb Z$ 1d reviewed Approve suggested edit on What powers of an $18$ cycle permutation are also $18$ cycles? 1d answered How can evaluate $\lim_{x\to0}\frac{3x^2}{\tan(x)\sin(x)}$? 1d revised How can evaluate $\lim_{x\to0}\frac{3x^2}{\tan(x)\sin(x)}$?Fixed TeX code for sin and tan 1d reviewed Approve suggested edit on What is $\sum_{i=1}^n \sqrt i$ 2d reviewed Approve suggested edit on Number of positive integers that cannot be expressed as $ax+by$ 2d revised Graphing $\sin(|x|)$?Replaced \operatorname{abs}(x) by |x| 2d comment Solve $\tanα+2\tan2α+4\tan4α+8\tan8α+16\tanα=\cotα$ for $\alpha$Is the equation right? $\tan\alpha+\dots+16\tan\alpha=$ 2d comment How to modify the headers of this book to lower case?Many thanks! Done, worked as expected. 2d comment How to modify the headers of this book to lower case?Is it possible to change the header from italic to normal, by adding some code? 2d revised Integrate ${\sec 4x}$Fixed spelling typo 2d revised How to evaluate the trigonometric integral $\int \frac{1}{\cos x+\tan x }dx$Fixed spelling typo and added link 2d answered How to evaluate the trigonometric integral $\int \frac{1}{\cos x+\tan x }dx$ Jun 15 reviewed Approve suggested edit on Probability (usage of recursion) Jun 15 revised How to evaluate the trigonometric integral $\int \frac{1}{\cos x+\tan x }dx$Added (calculus), (indefinite-integral) and (integral) tags Jun 15 reviewed Approve suggested edit on General solution of the equation $x_1 \cdots x_n + A = 0$ in complex numbers Jun 14 comment Fourier PropertiesDoes $f(x)*g(x)$ denotes the convolution $(f*g)(x) = \int_{-\infty}^\infty f(y)g(x - y)\,dy$ ?