I am having troubles with this problem. Translation: A metric $d$ on a continuum is called convex if for any two points $p$ and $q$ of $X$ there is a point $x\in X$ such that $d(p,x)=\frac12d(p,q)=d(q,x)$. Prove that if the metric on $X$ is convex, then the balls are connected, and $X$ is locally connected. […]

I am pretty good at Français. But I learned mathematics in English. Trying to translate mathematical statements from English to French can often be accompanied with many errors because the way mathematical statements are expressed is very different than the way usual statements in a particular language are expressed. Moreover, exact translation may often lead […]

I am deeply interested in Kolmogorov’s probability contest whose tests could be found in English for the five first years but there is no English translation to its problems from round 6 onward. I have put the links to the original Russian problems and would be grateful to the contribution of Russian speakers in this […]

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