We think about surfaces in different ways.

**Work in groups of 3–4, writing your answers on a separate sheet of
paper.**

### Considering tables

Let be a differentiable function that is roughly described by the following table of values:

If you were to leave the point in the direction of the gradient, what value would you
find?

**Explain why this makes sense.**### Considering level sets

Consider the following contour plot for :

If you were to leave the point in the direction of the gradient, what value would you
find?

**Explain why this makes sense.**### Considering algebra

Let be described by: As a gesture of friendship, we have included a graph :