From Section 3.1- Comparing Functions and Related Marginal Functions

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Section C.1 From Section 3.1- Comparing Functions and Related Marginal Functions

The spreadsheet skill in this section was to make a table and graph of a function and its related marginal function. This was done several ways.

Subsection C.1.1 Marginal Functions with \(q\) increasing by 1

The easist contruction is to build a table where the value of \(q\) increases by 1 3.1.4 from one row to the next. Since \(Mf(q+1)=f(q+1)-f(q)\text{,}\) we simply subtract values in successive rows 3.1.5. Screencast of eaxmaple using this approach. 3.1.3

Subsection C.1.2 Marginal Functions using Columns

The next easist contruction is to build a table computing \(f(q+1)\) and \(f(q)\) as separate columns with the cell reference replaced by the reference plus 1 3.1.13. Since \(Mf(q+1)=f(q+1)-f(q)\text{,}\) we simply subtract values in successive columns. Screencast of eaxmaple using this approach. 3.1.3

In practice, students often make formula mistakes when using this approach.

Subsection C.1.3 Marginal Functions using Quick Fill

The preferred construction builds a template that is easy to reuse. We set up successive colummes for , q, q+1, f(q) and f(q+1) 3.1.14. I then only have the enter the formula for the function one, under f(q). Quick fill then provides the correct formula for f(q+1). Screencast of eaxmaple using this approach. 3.1.12 The approach starts at the 3 minute markIn practice, students often make formula mistakes when using this approach.