Recent content by Quinzio

OK ok. I only wanted to give an easy way for uniform convergence for ##x \in [-\infty,0),(0,\infty]##. Then one should treat the zero as a special case.

You saw that p,q=1 is a sort of boundary value. Then it's worthwhile to investigate it deeper. You could check what happens if you hold still p=1 and change q, then q=1 and vary p.

Hi haruspex, It will converge in all reals but zero. That's why I'm saying the thesis is not true.

First of all the thesis that ##f_n(x)## in uniformly convergen on \mathbb{R} is not to be taken for sure. Those are not the only values by which ##f'(x)=0## Something went wrong during this step. You should get: ##\frac{\frac{1}{1-n}}{\left(1+\frac{1}{1-n}\right)^n}## and with some easy...

Because it's low but not zero.

For some of the items you may find helpful that sin(f(x)) is a bounded function.

Thanks everybody for shedding light. Some doubts remains. Everyone has experienced at least once that keeping a broom upside down supported by the palm of a hand is an embarassingly difficult task. Does the length of the object makes the task easier ? So, is it much more easy to balance a...

My question is: since there exists a Plank time and a Plank distance, is it true or false that any speed and the speed of light in particular must be a multiple of (Plank distance)/(Plank time) ? Am I saying something nonsense ?

The online edition of an italian newspaper, reported the curious event of a street pole which seems to vibrate for prolonged times, hours, even an entire day and without any clear reason. Someone talks about a building site in the nearby area, other talks about a wind turbulence called "vortex...

I'm not really close to you. I'm from Italy, city of Modena.

Yesterday I got fascinated by the camera recordings on the Atlantis Space Shuttle. I have two questions which I cannot give an answer. Maybe some of you may help. 1) Lift off: we can assume the big ship has its center of mass in the geometrical center. The force if applied in the lower end...

Yep, asymptotic comparison seems a good way.

I don't quite follow you. I sort of need simpler methods, thanks anyway.

Homework Statement Show that \sum_{k=0}^{\infty} \sqrt[k]k-1 converges. Homework Equations Ratio, radix theorems, comparison with other sums... The Attempt at a Solution No idea whatsoever. Where does one begin in this case ? With other cases I'm quite confident.

Well, I'll be not 100% accurate, but I suppose electrons in metals are not really free, but they are "shared" between adjacent atoms which have them in common on their external orbits. So electrons are free must they must still belong to an atom. To pull off electrons from metals, you need...