Let f:RoRf: \mathbb{R} o \mathbb{R}f:RoR be a function satisfying f(x)+f(y)=f(x+y)+xyf(x) + f(y) = f(x+y) + xyf(x)+f(y)=f(x+y)+xy for all x,y∈Rx, y \in \mathbb{R}x,y∈R. If f(1)=2f(1) = 2f(1)=2, what is the value of f(10)f(10)f(10)?
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66