BDMO 2019, National, Secondary Q. no. 9
Posted: Thu Dec 03, 2020 12:07 pm
[math] f(x+y) = xf(x)+2f(y)-x-y. f(2019) = a/b, a+b = ? [/math]
Take $y=2019$ and $x = 0$, then you will get $f(2019)$
But the function is wierd.
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