Find the range of the equation. f(x)=x²+4 Things I know for sure: x²>=0 We are brushing up on functions and interval notation in my calc class, and I can't remember how to do this in interval notation. If x is a number being squared it has to be positive or zero. So at the minimum the answer is going to be: f(x)=0+3 f(x)=3 So the interval notation would be what? Quick little explanation would help as well. Thanks.