Question

I solved this and think the range is: y>=3.Did I solve correctly?

Answer 1

Notice that

`\begin{gathered} x^2\ge0,x\in\Re \\ \Rightarrow x^2+3\ge3,x\in\Re \\ \Rightarrow f(x)\ge3,x\in\Re \end{gathered}`

Therefore, the range of the function is f(x)>=3, or [3,infinite)