Ask your self which equation you should use. Since it says F(3) then we have to find an equation that would fit this correctly. For example if we look at -X^2, X<-2 we could see that 3 is clearly not less than -2, leading to the conclusion that this is not the right equation.. If you look at the last equation it says that x has to be greater/equal to 0 which is true. So then we are left with the equation...
