Two young mathematicians discuss how to sketch the graphs of functions.
- Devyn
- Riley, I’ve been thinking about the derivative.
- Riley
- It’s all about change. It’s some “change-detector” tool for math.
- Devyn
- I know! What’s crazy is that you can use it as a tool for sniffing out dirt on functions.
- Riley
- First tells us increasing or decreasing.
- Devyn
- Then tells us concavity.
- Riley
- From just that we know all local maxes and mins.
- Devyn
- And if we use limits, we can find any asymptotes!
- Riley
- You know, I’d like to make up a procedure based on all these facts, that would tell me what the graph of any function would look like.
- Devyn
- Me too! Let’s get to work!
On some interval, we know that is positive and is positive. Which of the
following is the best option for the shape of the graph on that interval?