Here you can keep your brain fit by solving math related problems and also earn SBI by doing so.
The problems usually contain a mathematical equation that in my opinion is fun to solve or has an interesting solution.
I will also only choose problems that can be solved without additional tools(at least not if you can calculate basic stuff in your head), so don't grab your calculator, you won't need it.
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x = 20, y > -1. If there are multiple solutions submitted, that are part of the same general solution, they will be counted as one solution.↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓↑↓
It may look hard, because of the many 1/x, …, but they are easy to get rid of.
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You can take a look at the results of the last contest here. There you can also find out how I evaluate your entries.
To everyone who already participated in a past contest, come back today and try a new problem(tell me if you don't want to be tagged):
In case no one gets a result(which I doubt), I will give away the prize to anyone who comments.
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You can support him by using a witness vote on untersatz, so he can further support this and other contests.