A Functional Equation from British Math Olympiads 2009
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Simplifying a Viewer Suggested Algebraic Expression
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A Functional Equation from Putnam and Beyond
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A nice functional equation from Romania
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Looking for a function f
16:24
a functional equation
12:10
A Nice Functional Equation [f(x+y)=f(x)+f(y)+2xy]
12:43
A Cool Functional Equation
11:13