# Activities

• • • ##### Subject Area

• Math: Calculus: Derivatives

• ##### Author 9-12

60 Minutes

• ##### Device
• TI-89 / TI-89 Titanium
• TI-92 Plus / Voyage™ 200
• ##### Report an Issue

Use of CAS in teaching Differential Calculus by First Principle

#### Activity Overview

This Computer Algebra System (CAS) activity encourages students to investigate the use of CAS to solve functions using derivatives and appropriate formulas.

#### Before the Activity

• See the attached PDF file for detailed instructions for this activity
• Print pages 1 - 3 from the attached PDF file for the class
• #### During the Activity

Distribute the page to the class.

• Define a function and graph it
• Calculate the gradient between two points on the curve
• Animate the picture on the screen to demonstrate the secant approaching the tangent at a point on the curve
• Use CAS to find the gradient of the tangent to the function's curve
• Repeat steps for different functions
• Examine the change in calculations if the gradient is evaluated at a given point
• Understand that CAS eliminates the occurrence of incorrect evaluation and simplification of expressions
• #### After the Activity

Students answer questions on the Activity sheet.

Review student results:

• As a class, discuss questions that appeared to be more challenging
• Re-teach concepts as necessary