Related videos :
[ Ссылка ]
Without mathematical formulas.
Very simple, just use paper aids. The results are not very accurate, but good enough. May be useful.
![](https://i.ytimg.com/vi/7INBkEnG0hw/maxresdefault.jpg)
Related videos :
[ Ссылка ]
Without mathematical formulas.
Very simple, just use paper aids. The results are not very accurate, but good enough. May be useful.