Mathematik 4. Auflage

It's a great book about mathematics, though Springer has not provided an English version yet. I've just finished chapter #2 about Logic, Sets, and illustration of the language of mathematics. It's a great way to use German again and become familiar with German mathematical terms. I had to realise how many terms came from the German language to the Hungarian; dear Reader, did you know that German was the official language in Hungary until 1844?

So, about the book: It's a pretty good book, well edited, perfect for beginners/restarters like me as well.

I was reading about the countability of real numbers when I saw George Cantor's diagonal method as proof that the cardinality of real numbers is non-countable infinity. I have to admit I saw at first sight the proof is not correct. So, I started to google it and found the same result from many sources.

will be continued soon....