Math Contest #22 Results and Solution

Solution

The problem of this contest was to proof euler's function:

This can be done using taylor series at x = 0 because all 3 functions are continuous and have continuous derivatives:
You can see the taylor series as given, but they are on the other hand not too hard to construct because all three functions have cyclical repeating derivatives. And seeing that they are similar isn't that hard then:

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List of participants with their entries:

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Winner draw:

Not necessary since the reward can be divided be the number of entries:
Congratulations @kaeserotor and @crokkon , you won 1 SBI each!
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The next contest starts in 2 days. Don't miss it!