# Isn't it infinity?

Calculus Level 3

How many functions are there such that $$f''(x)>0$$ for every $$x>0$$, $$f(1)=-5$$ and $$f(2)=-11$$ and f(0)=0 ? If the number of functions is $$n$$, then submit your answer as $$n!+n-1$$.

Notation: $$f''(x)$$ means second derivative of $$f(x)$$.

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