Let f(x)= cases 2x^2-10x,&- <x -5 ^2-5,&-5<x<3 ^2+1,&3 x< cases

MATHEMATICS · Single correct · AoPS · Mathematics · Special Functions · Special Functions

Problem

Let

f(x)=\begin{cases}2x^2-10x,&-\infty<x\leq-5\\x^2-5,&-5<x<3\\x^2+1,&3\leq x<\infty\end{cases}.

The number of negative integers in the range of

f(x)

is (a) 6 (b) 5 (c) 4 (d) 3